SMITHSONIAN INSTITUTION
UNITED STATES NATIONAL MUSEUM
Bulletin 73

AN ACCOUNT OF THE BEAKED WHALES OF THE FAMILY ZIPHIIDÆ IN THE COLLECTION OF THE UNITED STATES NATIONAL MUSEUM, WITH REMARKS ON SOME SPECIMENS IN OTHER AMERICAN MUSEUMS

BY
FREDERICK W. TRUE
Head Curator, Department of Biology, U. S. National Museum

WASHINGTON
GOVERNMENT PRINTING OFFICE
1910

BULLETIN OF THE UNITED STATES NATIONAL MUSEUM
Issued September 28, 1910.

ADVERTISEMENT.

The scientific publications of the United States National Museum consist of two series, the Proceedings and the Bulletins.

The Proceedings, the first volume of which was issued in 1878, are intended primarily as a medium for the publication of original, and usually brief, papers based on the collections of the National Museum, presenting newly-acquired facts in zoology, geology, and anthropology, including descriptions of new forms of animals, and revisions of limited groups. One or two volumes are issued annually and distributed to libraries and scientific organizations. A limited number of copies of each paper, in pamphlet form, is distributed to specialists and others interested in the different subjects as soon as printed. The date of publication is printed on each paper, and these dates are also recorded in the tables of contents of the volume.

The Bulletins, the first of which was issued in 1875, consist of a series of separate publications comprising chiefly monographs of large zoological groups and other general systematic treatises (occasionally in several volumes), faunal works, reports of expeditions, and catalogues of type-specimens, special collections, etc. The majority of the volumes are octavos, but a quarto size has been adopted in a few instances in which large plates were regarded as indispensable.

Since 1902 a series of octavo volumes containing papers relating to the botanical collections of the Museum, and known as the Contributions from the National Herbarium, has been published as bulletins.

The present work forms No. 73 of the Bulletin series.

Richard Rathbun,
Assistant Secretary, Smithsonian Institution,
In charge of the United States National Museum.

Washington, D. C., June 1, 1910.

TABLE OF CONTENTS.

Page. [Introduction] 1 [Descriptions of skulls and skeletons of Ziphioid whales] 3 [Genus Mesoplodon] 3 [Mesoplodon bidens] 4 [densirostris] 9 [europæus] 11 [stejnegeri] 24 [Genus Ziphius] 30 [Ziphius cavirostris] 30 [Genus Berardius] 60 [Berardius bairdii] 60 [Genus Hyperoödon] 76 [Hyperoödon ampullatus] 76 [List of species of existing Ziphioid whales] 76 [Index] 79 [Explanation of plates] 83

AN ACCOUNT OF THE BEAKED WHALES OF THE FAMILY ZIPHIIDÆ IN THE COLLECTION OF THE UNITED STATES NATIONAL MUSEUM, WITH REMARKS ON SOME SPECIMENS IN OTHER AMERICAN MUSEUMS.

By Frederick W. True,
Head Curator, Department of Biology, U. S. National Museum.

INTRODUCTION.

The beaked whales belonging to the family Ziphiidæ are, with the exception of the bottle-nosed whales of the genus Hyperoödon, among the rarest of cetaceans. Of the three genera Mesoplodon, Ziphius, and Berardius, so far as I have been able to ascertain from published records, specimens representing about one hundred individuals are known, and somewhat more than one-half of these belong to the first-named genus. Berardius is the rarest genus, only about fourteen specimens having been collected thus far. The U. S. National Museum contains specimens representing some twenty-five individuals of the three genera, or about one-fourth of the material at present available. Among these are six specimens of the genus Berardius, or nearly half of all that have been recorded thus far.

The most important addition to the knowledge of these whales made during the last quarter century was the discovery of representatives of the three genera Mesoplodon, Ziphius, and Berardius, at Bering Island, in the North Pacific, by Dr. Leonhard Stejneger, whereby the known range of the family was very greatly extended. Two of the forms were described by Doctor Stejneger in 1883, and the third by myself from a skull which he collected. About one-half of the material which the Museum possesses consists of that collected by Doctor Stejneger in Bering Island and that from the same locality presented by Mr. Nicholas Grebnitzki, Russian governor of the Commander Islands.

About six years ago the National Museum received information and specimens from correspondents showing that the range of the three genera found at Bering Island extends to the eastern North Pacific, one genus (Ziphius) having been observed at Kiska Harbor, Alaska, another (Mesoplodon) at Yaquina Bay, Oregon, and the third (Berardius) at St. George Island, Pribilof Group, Alaska, and near Cape Mendocino, California.

On the east and west coasts of the United States the only occurrences of beaked whales known to me are as follows:

EAST COAST OF THE UNITED STATES.

Mesoplodon bidens: Nantucket Island, Massachusetts. 1867. Skull in the Museum of Comparative Zoölogy, Cambridge, Massachusetts. Mesoplodon europæus: Atlantic City, New Jersey. March 28, 1889. Young male. Skeleton, cast, photographs, and viscera in the National Museum. North Long Branch, New Jersey. July 22, 1905. Adult female. Skull in the Museum of Comparative Zoölogy, Cambridge, Massachusetts. Mesoplodon densirostris?: Annisquam, Massachusetts. August, 1898. Young female. Skeleton in the Museum of the Boston Society of Natural History. Ziphius cavirostris: Charleston, South Carolina. 1865 (?). Young female. Skeleton in the National Museum. (Type of Z. semijunctus.) Barnegat City, New Jersey. October 3, 1883. Adult female. Skeleton and cast in the National Museum. St. Simon Island, Georgia. 1893. Male (?). Known from a photograph; only a few bones preserved. Newport, Rhode Island. October, 1901. Adult male. Skeleton and photograph in the National Museum. Hyperoödon ampullatus: New York Bay, New York. 1822. Female (?). Not known to have been preserved. North Dennis, Massachusetts. January, 1869. Male. Skeleton in the Museum of Comparative Zoölogy, Cambridge, Massachusetts. Newport, Rhode Island. 1869. Female. Skull in Museum of the Academy of Natural Sciences, Philadelphia.

WEST COAST OF THE UNITED STATES.

Mesoplodon stejnegeri: Yaquina Bay, near Newport, Oregon. February 15 (?), 1904. Adult. Skull in the National Museum. Ziphius cavirostris: Kiska Harbor, Alaska. September, 1904. Known only from photographs. Berardius bairdii: St. George Island, Pribilof Group, Alaska. June, 1903. Adult female. Skeleton in the National Museum. St. George Island, Pribilof Group, Alaska. June, 1903. Young male. Skeleton in the National Museum. Centerville Beach, near Ferndale, California. October, 1904. Adult male. Skeleton in the National Museum. Alaska or California (?). Skull formerly in museum of the Alaska Commercial Company, San Francisco. Trinidad, California. January 30, 1905. Not preserved; perhaps not this genus. St. George Island, Pribilof Group, Alaska. August 21, 1909. Female. Probably not preserved. Reported by Maj. Ezra W. Clark.

DESCRIPTIONS OF SKULLS AND SKELETONS OF ZIPHIOID WHALES.

Genus MESOPLODON Gervais.

Of this genus the National Museum has four specimens; namely, (1) a skull (Cat. No. 21112, U.S.N.M.) obtained at Bering Island, North Pacific Ocean, in 1883, by Dr. L. Stejneger, and made the type of the species M. stejnegeri True; (2) a skull and photographs (Cat. No. 143132, U.S.N.M.) of the same species, from Yaquina Bay, Oregon, obtained in exchange from Mr. J. G. Crawford in 1904; (3) a skeleton, cast, and photographs of a young male (Cat. No. 23346, U.S.N.M.), hitherto supposed to represent M. bidens, caught at Atlantic City, New Jersey, in 1889; and (4) a skeleton of an adult (Cat. No. 49880, U.S.N.M.) from the Chatham Islands, New Zealand, representing M. grayi.[1]

In addition to this material, I have had the privilege of examining two skulls belonging to the Museum of Comparative Zoölogy, and hitherto supposed to represent M. bidens, and two skeletons belonging to the American Museum of Natural History. Of these last, one is that of an adult and was purchased by the American Museum under the name of M. layardi, but was subsequently recognized to be a new species and was described by Mr. Andrews, under the name of Mesoplodon bowdoini. The other is that of a young individual, and has been labeled M. grayi.

As already noted by Dr. G. M. Allen,[2] only four specimens of Mesoplodon have been recorded hitherto from the Atlantic coast of the United States. These are:

1. An adult, sex unknown, but probably female, 16 feet long, found at Nantucket, Massachusetts, in 1867, and recorded by Prof. L. Agassiz.[3] The skull of this individual is in the Museum of Comparative Zoölogy, Cambridge, Massachusetts.

2. A young male, 12½ feet long, captured at Atlantic City, New Jersey, March 28, 1889. The skeleton (Cat. No. 23346, U.S.N.M.) is in the National Museum.

3. A young female, 12 feet 2 inches long, stranded at Annisquam, Massachusetts, August, 1898, and recorded by the late Alpheus Hyatt.[4] The skeleton is in the museum of the Boston Society of Natural History.

4. An adult female, said by fishermen who measured it to have been 22 feet long, entangled in pound nets at North Long Branch, New Jersey, July 22, 1905, and recorded by Dr. Glover M. Allen.[5] The cranium of this individual is preserved in the Museum of Comparative Zoölogy. The rostrum and mandible, which were originally obtained, were afterwards destroyed by accident.

I have examined all this material. Writers who have had occasion to mention these four specimens thus far have referred them tacitly to Mesoplodon bidens (Sowerby), but, after a careful study of them, I have ascertained that while the Nantucket specimen belongs to that species, the Atlantic City and Long Branch specimens represent Mesoplodon europæus (Gervais). This is a very interesting discovery, because the latter species has been known hitherto only from a single skull, and its validity has been frequently questioned. The Annisquam specimen, as will be seen later, presents characters which appear to ally it to M. densirostris.

MESOPLODON BIDENS (Sowerby).

Physeter bidens Sowerby, British Miscell., 1804, p. 1; Trans. Linn. Soc. London, vol. 7, 1804, p. 310. Delphinus sowerbensis Blainville, Nouv. Dict. Hist. Nat., 2d ed., vol. 9, 1817, p. 177. Delphinus sowerbyi Desmarest, Mammalogie, pt. 2, 1822, p. 521.

The only specimen from the Atlantic coast of the United States which can with certainty be referred to this species is the one from Nantucket mentioned on page 3. Prof. L. Agassiz’s original notice of it is so brief that it is quoted in full below:

Professor Agassiz also brought to the notice of the Society the discovery of a Cetacean, new to America. The skull was exhibited, and its peculiar features pointed out. It was obtained on the coast of Nantucket by Messrs. H. M. and S. C. Martin, of Roxbury. It belonged to the genus Mesoplodon, as characterized by Gervais, and ought to be separated from the fossil Ziphius, described by Cuvier. Professor Agassiz, however, questioned whether Mesoplodon was not identical with Delphinorhynchus, previously described by De Blainville. The specimen found at Nantucket measured 16 feet in length.[6]

SKULL.

The skull of this Nantucket specimen, which I have before me, is thoroughly adult. That the specimen is a female is probable from the fact that the teeth (one of which is preserved), though fully developed, are only two-thirds as broad and three-fourths as long as those of Sowerby’s specimen (the type of the species), which was an adult male.[7] The skull is 765 mm. long, and about 30 mm. are lacking from the end of the beak, so that the original length was about 795 mm. It appears to be, therefore, rather the largest skull of the species of which there is any record. The specimen itself, according to Dr. J. A. Allen, was 16 feet 3 inches long.[8] The largest European skull appears to be the one in the Edinburgh Museum, described by Sir William Turner in 1872.[9] The length of this is 749 mm. The specimen was a female, but though the skull is so large, the mesirostral cartilage was not ossified, and the individual was, therefore, probably not thoroughly adult. Two other European specimens, of which the total length was almost identical with that of the Nantucket specimen, were (1) the adult female obtained at Overstrand, England, in 1892, and recorded by Southwell and Harmer[10] (length 16 feet 2 inches, straight); (2) the adult male obtained at Brodie House, Scotland, in 1800, and recorded by Sowerby[11] (length 16 feet). The length of the skull is not given for either of these specimens. The adult male obtained at Rugsund, Norway, in 1901, and recorded by Grieg,[12] was only 15 feet 1 inch long, but some of the measurements of the skull are as large as, or even a little larger than, those of the Nantucket skull. The total length of the skull was not given, as the end of the beak was lacking.

Grieg’s figures of the Rugsund skull afford a very satisfactory basis for comparisons between that specimen and the Nantucket skull ([Pl. 1], fig. 1). Both skulls show the comparatively narrow frontal region, the moderately developed tubercle anterior to the anteorbital notch, and the low maxillary ridge, which are characteristic of the species. In both skulls the anterior prolongation of the ethmoid is lanceolate and flat, but in the Rugsund skull the apex is truncated. In the latter also the posterior end of the mesirostral ossification is divided into three longitudinal sections by two lateral and somewhat divergent grooves, while in the Nantucket skull there is only a single median groove. These differences may safely be regarded as individual. Toward the distal end the surface of the ossification in the Nantucket is pitted and irregular and descends much below the level of the premaxillæ. It ends distally at the same point with the vomer. In this skull the proximal end of the premaxillæ and adjoining plate of the maxillæ are somewhat less reflexed than in the Rugsund skull. The shape of the superior margin of the supraoccipital is alike in both.

There are no well-defined differences in the relative thickness of the beak at the base or in the form and position of the visible portion of the palatines, but in the Nantucket skull the mass of the combined frontal and lachrymal anterior to the orbit is less rounded and more triangular than in the Rugsund skull. The temporal fossæ also have a postero-superior angular enlargement not seen in the latter.

In the Nantucket skull the rostral portion of the premaxillæ is high and at the distal end vertical. The superior profile is somewhat convex, and the superior free margin rounded proximally, but sharp distally. The least distance between the free margins is 10 mm.

The pterygoids are cut off from the maxillæ anteriorly by a very narrow band of the palatine, which connects with a broad band externally and a lanceolate segment internally. The inferior pterygoid ridges diverge anteriorly. The broad surface internal to them is concave. The external border of the pterygoid sinus is nearly straight. An elongated, fusiform section of the vomer is visible on the inferior surface of the beak at the middle for a distance of 158 mm., and a small lozenge-shaped section, ill defined, is visible between the pterygoids and palatines. ([Pl. 4], fig. 1.)

The expanded anterior end of the malar is rhomboidal in form, with an external free margin 11 mm. long. Anteriorly it does not form part of the margin of the anteorbital notch.

The lachrymal is irregularly oblong, with an external free margin 35 mm. long and 12 mm. thick. The distance from the anteorbital notch to the anterior end of the orbit is 60 mm. ([Pl. 7], fig. 1.)

The lateral free margins of the basioccipital are extended posteriorly beyond the exoccipitals, which is a character indicative of age.

The supraoccipital has a distinct median ridge, with a longitudinal depression on each side, bounded externally by a prominent convexity. ([Pl. 10], fig. 1.)

MANDIBLE.

The mandible is slender, with a very elongate symphysis, which measures 237 mm. The inferior outline of the ramus is strongly concave at the middle and slightly convex posteriorly, while the symphysial portion is bent upward. The superior outline is concave both behind and before the tooth, and also immediately anterior to the coronoid process. At about the beginning of the posterior fourth the outline is convex, and the mandible at this point is nearly as deep as at the coronoid process. The superior surface of the symphysis slopes down on each side to the median line, but each half of the surface is itself nearly plane. ([Pl. 11], figs. 1, 2, and 5.)

The alveolar groove anterior to the tooth is very distinct throughout and is without septa and open at the bottom. It ends distally in a rounded aperture 6 mm. in diameter, below which are several small foramina. These lead to a very large canal which occupies all the symphysial portion of the mandible, the walls being comparatively thin. Behind the tooth the alveolar groove becomes narrower gradually and disappears in a length of about 140 mm.

The mental foramen is situated in line with the anterior base of the tooth, and is confluent with a groove which extends forward for about 80 mm. A rather shallow groove runs along the inferior margin of the symphysis.

The coronoid process is erect and rounded, and is joined by a horizontal ridge anteriorly.

TEETH.

The mandibular tooth, which is shown in [Pl. 2], fig. 3, is preserved on the right side only. Its dimensions are as follows: Length anteriorly in a straight line, 75 mm.; length from the apex to the posterior end of the root, straight, 60; greatest antero-posterior breadth, 28; transverse thickness, 10; height of apex above internal superior margin of jaw when tooth is in situ,[13] 22; antero-posterior length of base of exposed portion, 30; distance from anterior end to posterior end of root, 37; greatest height of the exposed dentine crown, above the cement, 14; length of the base of the dentine crown, 12.

This tooth, as already stated, is only two-thirds as broad and three-fourths as long as that of Sowerby’s Brodie House specimen (the type of the species), which was an adult male, and leads to the belief that the Nantucket specimen was a female. This is in a manner confirmed by the Rugsund specimen, which was an adult male and had teeth as large as Sowerby’s specimen. It has to be remarked, however, that in the Overstrand, England, specimen (1892), which was an adult female, the teeth did not project beyond the gums. Messrs. Southwell and Harmer say regarding it:

The jaws were apparently completely edentulous, and although it was possible to feel through the gums a slight prominence on either side in the position of the teeth of the male, we could not by this means definitely satisfy ourselves with respect to this point, nor were we able to ascertain the presence of any other rudimentary teeth in either jaw. The evidence which exists on this subject is favourable to the view that the female of this species is not provided with any teeth which are large enough to pierce the gums.[14]

It is probable that the teeth in the Nantucket specimen, though quite large, did not project beyond the gums any considerable distance. The external border of the alveolar groove behind the tooth is only 20 mm. below the apex of the tooth, and it is not unlikely that the gums in a specimen of this size had nearly that thickness, so that only the tip of the tooth would project beyond them. Though the apex is acute, it has a flat abraded surface anteriorly, which, however, is but 4 mm. long. It seems probable, on the whole, that the teeth in the female may be quite large without projecting more than a few millimeters beyond the gums.

In shape the tooth of the Nantucket specimen is almost identical with that of Sowerby’s Brodie House adult male, as figured by Lankester. The dentine at the apex is more nearly white than the cement which surrounds it. The superior margin of the latter is not a plain ring, but sends upward a papilliform projection on each side. The dentine itself has two vertical grooves on each side. The root of the tooth ends very obliquely and is rugose and irregular. The cavity is closed.

Grieg remarks as follows regarding the structure of the teeth of the Rugsund specimen:

Sections and microscopic preparations of the alveolar tooth of this whale show that its apex consists of dentine, within which is found an inner pulp cavity 4 mm. long and 1 mm. broad. The dentine, the structure of which agrees with that which Turner found in Mesoplodon bidens and Mesoplodon layardi, is yellowish white, with the exception of the part nearest the pulp cavity, which is yellowish brown. It seems to correspond most closely to what Ray Lankester called osteodentine. Throughout the tooth the dentine is covered with a very thin layer of shining white enamel. The enamel is, however, lacking on the front of the tooth, having probably been worn away. A section through the middle of the tooth, at right angles with the V-shaped furrow, shows a yellowish cement layer from 3 to 5 mm. broad, which is, however, worn away on the front of the tooth. Within the cement layer is a white, amorphous, calcareous mass, forming a band from 1.5 to 3.5 mm. broad, which appears to correspond to Ray Lankester’s “globular matter” and Turner’s “modified vasodentine.” The mass seems to agree most closely with Ray Lankester’s “globular matter,” as it has “no structure excepting an indistinct botryoidal character visible with a low magnifying power.” The core of the tooth consists of dentine, the inner layer of which is brownish, while the outer is rather whitish yellow. As above mentioned, the dentine is visible on the front of the tooth, since both the cement and the amorphous, calcareous mass are worn away. Moreover, it is clear that on the front of the tooth the dentine is not covered by enamel. The pulp cavity is reduced to a fine pore. A section across the root of the tooth shows an outer yellowish cement layer, from 2 to 5 mm. broad, while the interior of the tooth is filled with a white, amorphous, calcareous mass, which is interspersed with thin yellowish lamellæ of dentine. Here and there, also, thin lamellæ are seen to extend from the outer cement layer into the white, amorphous, calcareous mass. The dentine lamellæ appear to be identical with what Ray Lankester calls osteodentine. No pulp cavity is visible in the root of the tooth.[15]

The dimensions of the Nantucket skull are given in the following table in comparison with those of seven European skulls of M. bidens. Dimensions of the Annisquam, Massachusetts, skull are also added for purposes of comparison, although it represents another species (see [p. 9]).

Dimensions of eight skulls of Mesoplodon bidens and one skull of M. densirostris (?).

Column headings: M. bidens. B: Nantucket, Massachusetts, 1867, M.C.Z., female? adult.^a C: Scotland, 1872, Turner, female young.? D: Fæø, Norway, 1895, Grieg, female? young. E: Shetland, 1881, Turner, male adult. F: Rugsund, Norway, 1901, Grieg, male adult. G: Udsire, Norway, 1869, Malm, male (No. 1). H: Vanholmen, Sweden, 1881, Malm, male (No. 2). I: Landenæs, Norway, 1895, Grieg, male. M. densirostris. (?) J: Annisquam, Massachusetts, 1898, True, female young.

^a The size of the teeth makes it quite certain that it is an adult female. ^b End of beak broken off about 30 mm. from tip. ^c Right side. Add 31 mm. for breakage. ^d In median line. ^e At middle. ^f Between “suprafrontal processes of max.” ^g Grieg’s fig., p. 18, shows 44 mm. ^h From Grieg’s fig., p. 18. ⁱ “Length of ramus.” Length of mandible=699 mm. ^j In Trans. Roy. Soc. Edinburgh, vol. 26, 1872, p. 776.

MESOPLODON DENSIROSTRIS (Blainville)?

Delphinus densirostris Blainville, Nouv. Dict. Hist. Nat., 2d ed., vol. 9, 1817, p. 178. Ziphius seychellensis Gray, Zoöl. Erebus and Terror, 1846, p. 28.

The skull of the specimen from Annisquam, Mass., ([Pl. 1], fig. 2) is, I regret to say, in rather poor condition. It is broken in the left orbital region, and all the bones, especially those of the beak, are warped by weathering. The proximal extremity of the left premaxilla is lacking and also the tip of the beak.

The skull is obviously that of a young animal, as all the sutures are open and the surface of the occipital condyles is pitted, owing to imperfect ossification.

Although the dimensions of the skull, with a few exceptions, agree well with those of young specimens of M. bidens, as shown by the foregoing table (p. 8), certain differences stand out conspicuously. The most salient of these is the depth of the beak as a whole and the depth and shape of the rostral portion of the premaxillæ. The latter portion of the premaxillæ instead of being low, with a straight inferior margin, is very high, with the inferior margin strongly convex. At the middle of the beak the premaxillæ are higher than the maxillæ on which they rest. It is true that the shape of the beak varies greatly with age in bidens and other species of Mesoplodon, but I do not find any evidence that such a change as is here indicated takes place in bidens. The form of the beak and of the rostral portion of the premaxillæ is that of M. densirostris.

The beak is almost as broad at the base as in bidens, but the lateral free margin of the maxilla anterior to the anteorbital notch instead of continuing along the side of the beak nearly to the tip, as in bidens, ends at a point about 90 mm. in front of the line of the notch, beyond which the sides of the beak are vertical.

The margin of the maxilla immediately anterior to the anteorbital notch is a little damaged, but there was apparently no strong tubercle at this point, and the surface of the maxilla, though convex, is not raised into a distinct ridge. In a young skull, however, one would not expect to find a high ridge. The palatines are visible from above, which is not the case in bidens.

The maxillary foramen is situated a little in advance of the premaxillary foramen and is directed forward, and, as Dr. Glover M. Allen has pointed out, connects with a broad groove which runs forward along the triangular, horizontal portion of the maxilla at the base of the beak. The maxillæ are much broader behind the notch than in bidens, and the anterior end of the malar forms the bottom of the notch. The premaxillæ are noticeably constricted immediately in front of the premaxillary foramina, and the expanded portion just behind these foramina is nearly horizontal, with a low transverse ridge near the middle. The proximal end of the premaxillæ is nearly vertical. The anterior nares are noticeably small. The foramen magnum is large, with a trifoliate outline ([Pl. 10], fig. 2). The palate at the proximal end presents a median ridge with a narrow groove on each side. The palatines extend as a broad band much beyond the pterygoids anteriorly. The vomer is visible below for a space of 142 mm. near the end of the beak. A very small piece is also visible at the base of the beak, between the palatines and pterygoids. The inferior surface of the pterygoids is convex on the side adjoining the lateral free margin ([Pl. 4], fig. 2).

This skull is peculiar in that there is no very distinct basirostral groove and that the basirostral ridge, as already stated, extends forward only about 90 mm. Below this ridge is a shallow broad groove which narrows rapidly forward and can be traced to the extremity of the beak, where it broadens out somewhat ([Pl. 7], fig. 2).

While this skull agrees in size and in many of its proportions with similar skulls of M. bidens, it differs from that species and agrees with M. densirostris in the breadth across the anteorbital region, in the depth of the beak and its shape at the base, in the shape of the premaxillæ both distally and proximally, in the direction of the maxillary foramen, and the shape of the maxillary bone in front of the same, in the occupation of the base of the maxillary notch by the anterior end of the malar, in the absence of any distinct maxillary ridge above the notch, in the forward extension of the palatines, and in the shape of the foramen magnum.

Flower states that there is a deep basirostral groove in M. densirostris,[16] but neither the figure in Gervais’ Zoologie et Paleontologie Française,[17] nor that in Van Beneden and Gervais’ Ostéographie des Cétacés,[18] shows such a groove. The conformation of the base of the rostrum appears to be about the same as in the Annisquam skull.

In regard to differences between this skull and those of M. densirostris it should be stated that in the latter the premaxillary foramina are situated farther apart, and that the maxillary foramina are situated considerably in advance of those of the premaxillæ instead of nearly in line with them.

The Annisquam skull approaches M. europæus in several characters, but these are such as europæus shares with densirostris. The principal ones are the breadth of the maxillæ in front of the orbits, the presence of the malar in the base of the anteorbital notch, and the convexity of a part of the inferior surface of the pterygoids.

Dr. Glover M. Allen has given an account of the exterior, skeleton, and teeth of this specimen, from which the following particulars are extracted:[19]

Regarding the Annisquam specimen no color notes were taken, but from a few small photographs in the possession of the Boston Society of Natural History, it appears evident that the ventral portion was of a lighter tint, and in one of the views a few oval whitish spots are seen on the side a trifle behind the middle portion of the body. Another view shows the convexity of the posterior margin of the flukes at the median point, as well as the prominent dorsal fin. The lower jaw protruded slightly beyond the upper. Measurements of this specimen, as noted by Professor Hyatt, are as follows: Total length, 12 feet 2 inches; from anus to bight of flukes, 3 feet 4 to 6 inches; across flukes, 3 feet 1 inch; from tip of rostrum to angle of mouth, 1 foot 1½ inches. The gular furrows were noted as about 10 inches long and from ¼ to ½ an inch deep.

The teeth of the Annisquam specimen barely projected above the alveoli of the jaws and are sharply mucronate. The basal portion of each, however, is more like that of the male’s tooth [M. europæus] in the slightly convex posterior outline and the forward extension of the anterior angle. * * *

The Annisquam skeleton has 45 vertebræ. Four of the seven cervicals are fused. The atlas, axis, and third cervical are firmly anchylosed throughout, save for the lateral foramina for the passage of the cervical nerves. The fourth cervical is fused to the third by the dorsal spine on the left side and by the tip of the upper lateral process of the same side. Its centrum, right half of the dorsal spine (the spine is divided medially), and the remaining lateral processes are free. * * * The epiphyses of the fourth and fifth cervical vertebræ and the anterior epiphysis of the sixth cervical are fused to their respective centra, but all the other epiphyses of the vertebral column and of the pectoral limbs are free.

The Annisquam skeleton has nine dorsal vertebræ with their corresponding pairs of ribs. * * * The sternum of this specimen presents few points of interest. It consists of four pieces, the anterior-most of which is largest, slightly hollowed above, and correspondingly convex below. The three remaining pieces are nearly flat, with a deep median notch at the anterior and posterior border of each. The posterior piece evidently represents a fusion of the elements of two segments, as there are articular surfaces for two pairs of ribs.

From the foregoing, it appears that the Annisquam specimen probably had one or two vertebræ less than bidens or europæus, and that the sternum was somewhat differently shaped. The tooth, which is figured by Doctor Allen, is conical, compressed, 54 mm. long, 30 broad at the base, and resembles teeth of immature bidens.

Although with such scant material it is not possible to determine satisfactorily the identity of this third species of Mesoplodon in the North Atlantic, represented by the Annisquam specimen, I feel convinced that that specimen does not belong to M. bidens and that there is a strong probability that it belongs to M. densirostris. It is true that the latter species has been found hitherto only in the Indian Ocean and about Australia, but we know so little about the distribution of the ziphioid whales that, in my opinion, that circumstance by itself should not be given very great weight.

MESOPLODON EUROPÆUS (Gervais).

Dioplodon europæus Gervais, Zool. et Pal. franç., 1st ed., vol. 2, 1848-1852, p. 4; 2d ed., 1859, p. 289, pl. 40, figs. 3-6. Dioplodon gervaisi Deslongchamps, Bull. Soc. Linn. Normandie, vol. 10, 1866, p. 177. Neoziphius europæus Gray, Suppl. Cat. Seals and Whales Brit. Mus., 1871, p. 101.

This species was based on a single specimen found floating in the English Channel about seventy years ago. An account of the circumstances under which it was found was given by Eugène Deslongchamps in 1866, as follows:

The head, which forms the subject of this last note, was given to my father some twenty-five or thirty years ago by Mr. Abel Vautier, a merchant and armorer of our town, who died at Paris two years since.

The captain of one of Mr. Vautier’s ships, on his return from a voyage to the colonies, saw floating on the water, at the entrance to the English Channel, the body of a large animal entirely covered by birds (large and small gulls, etc.), which were devouring it. The ship approached the stray, and the captain, knowing that Mr. Abel Vautier was greatly interested in natural objects, had the head of the cetacean cut off, fastened it securely with a cord, and let it trail behind the ship. When he arrived at Caën he made a present of it to Mr. Vautier. The piece had at that time an appearance anything but agreeable. Mr. Vautier was especially fond of beautiful objects which please the eye, and hence he offered it to my father, saying, “You, who are an anatomist, can make better use of this than I can.” My father was unwilling to refuse the present, but neither he nor Mr. Vautier knew as yet of its extreme rarity. It is in fact, up to the present time, the only specimen which exists, and is a unique object in collections.[20]

No additional specimens have been recorded from European waters or elsewhere, and much doubt has been thrown on the validity of the species, many zoologists regarding it as an adult of the commoner species M. bidens. Van Beneden remarked in 1888:

The opinions of naturalists are divided as regards the identity of this ziphioid, which is unique up to the present time. In the eyes of some it represents an old male of the common Mesoplodon, in which the tooth, instead of developing near the middle of the jaw, has developed near the anterior extremity. This is the opinion of Doctor Fischer and others, who think that this unique specimen represents merely an individual modification and that consequently it should not figure in the list of species. We do not share this opinion. It is not impossible that this ziphioid may belong to the other hemisphere, and this would explain why only one single individual has been captured in Europe.[21]

In view of the circumstances surrounding the discovery of the original specimen, it is of great interest to find that two of the specimens from the east coast of the United States represent the same species. As one of them is adult and the other young, the view that the type of M. europæus is merely an old individual of M. bidens is satisfactorily disposed of, as is also the opinion that it represents a singular individual variation.

The two American specimens which represent europæus are those from North Long Branch, New Jersey (adult female; skull, lacking rostrum and mandible, in the Museum of Comparative Zoology), and from Atlantic City, New Jersey (young male; skeleton, cast and photographs in the U. S. National Museum, Cat. No. 23346).

SPECIFIC CHARACTERS.

The species europæus differs from bidens in the following characters, which may be regarded as diagnostic:

Size larger and pectoral limbs relatively shorter and narrower.

The expanded portion of the maxillæ and frontals broader in front of the orbit. The protuberance which projects into the anteorbital notch much larger and the ridge on the maxilla which extends backward from it much higher. Distance from inner margin of maxillary foramen to tip of protuberance much more than one-half the distance between the maxillary foramina of the two sides. Rostrum deeper at the base. Inferior surface of pterygoids more or less convex, with a ridge (in adults) running diagonally across it.

The cranial characters above enumerated are found in the type-skull, as will be seen by examining the excellent figures in Van Beneden and Gervais’ Osteography, plate 24.

In Dr. Glover M. Allen’s account of the Long Branch specimen[22] it is stated that the fishermen who measured it reported that it was 22 feet long, while none of the European specimens (some of which were certainly adults) was more than 16½ feet long. That the measurement reported by the fishermen is at least approximately correct appears from the fact that the skull is larger than that of any of the European specimens. The beak is missing, so that the total length of the skull can not be given, but the distance from the occipital condyles to the line of the maxillary notches (straight) is 312 mm., while in the largest adult among the European specimens this distance is only 260 mm., and in the thoroughly adult Nantucket specimen 282 mm.

SKULL.

The Atlantic City and Long Branch skulls also agree in numerous other details of structure in addition to the foregoing, the more important of which will now be mentioned. Unless otherwise stated, the type-skull, as shown by Van Beneden and Gervais’ figures,[23] also presents the same peculiarities in contrast with M. bidens.

Dorsal aspect ([Pl. 2], figs. 1 and 2).—The premaxillæ are more depressed immediately in front of the blowhole than in M. bidens, which, with the prominence of the maxillary ridges, makes this whole region appear strongly concave. The blowhole is narrower absolutely and also relatively to the breadth of the expanded proximal ends of the premaxillæ, so that while in bidens the breadth of the blowhole is much more than one-third the breadth across the proximal ends of the premaxillæ, in europæus it is considerably less than a third. Both premaxillæ are much constricted on the sides of the blowhole and the effect is heightened by the greater expansion of the proximal ends of the former. These ends do not fit closely against the adjoining edge of the maxillæ as in bidens, but leave a transverse vacuity, or trough, which is especially noticeable in the type-skull. The anterior end of the malar bone occupies the bottom of the maxillary notch and a small portion of it is visible from above, while in bidens it does not extend up into the notch at all from the inferior surface and is not visible from above. The posterior margin of the maxillæ is more squared in europæus than in bidens.

The margins of the beak, formed by the maxillæ, instead of being straight, are somewhat emarginate a little posterior to the middle of the length and somewhat convex anterior to it, which gives the contour of the beak, seen from above, a different shape from that of bidens. In the type-skull of europæus the mesirostral ossification appears to be higher at the proximal end than the premaxillæ, and distally extends to the end of the beak. In bidens it is lower than the premaxillæ and, in the Nantucket skull at least, ends anteriorly at the same point as the vomer, or, in other words, much behind the end of the beak. It would appear from the statements of Sir William Turner, Van Beneden and Gervais, Grieg, and others, that the mesirostral ossification never reaches the end of the beak in bidens, but it does in grayi, haasti, densirostris, and many fossil species, as well as in europæus.

Lateral aspect ([Pl. 8], figs. 1, 2).—The temporal fossæ are a little longer than the orbit in europæus, but a little shorter than the orbit in bidens; in the former the superior margin is flat or a little concave, rather than convex. The exoccipital extends in an angle farther forward in europæus, and the suture between it and the zygomatic is, in consequence, less nearly vertical than in bidens. The premaxillæ at the sides of the blowhole are nearly horizontal, so that their superior surface is little seen from this aspect, while in bidens they slope downward, so that the whole of the superior surface is visible. The high maxillary ridge, situated behind the anteorbital notch, is very noticeable from this point of view, as it shuts off a considerable portion of the premaxillæ. The convex inferior outline of the beak and its great depth at the base are also salient peculiarities.

Ventral aspect ([Pl. 5], figs. 1, 2).—The anterior ends of the palatine bones are bifurcated, the inner part being the smaller. The two bones make but a narrow angle with the median line, instead of a wide one, as in bidens, and the surface of the maxillæ between them is strongly convex instead of flat. This convexity is narrowed at both ends, or, in other words, is fusiform in shape. No similar conformation is found in bidens, in which the inferior basal area of the maxillæ is flat.

In the young Atlantic City skull of europæus, the vomer is visible as a small, narrow, club-shaped piece, 68 mm. long. Anteriorly it joins the premaxillæ, which form a prominent ridge in the median line. On each side of this ridge is a wide and quite deep groove. As the beak is lacking in the adult North Long Branch skull, its peculiarities can not be made known. In the type-skull the form is the same as in the Atlantic City skull, but the vomer does not appear at all on the palate. In bidens the shape of the inferior surface of the premaxillæ at the distal end is quite different. A very narrow groove runs parallel with and close to the median line and the whole surface external to it is more or less convex.

MANDIBLE.

The mandible of the Atlantic City specimen of M. europæus resembles that of the type, as figured by Van Beneden and Gervais, in the shortness of the symphysis and in the position of the tooth, which is in advance of the posterior end of the symphysis. A number of differences, however, require consideration. ([Pl. 11], figs. 3 and 6.)

In the type, the symphysis, as shown by Van Beneden and Gervais’ figure, plate 24, fig. 2a, is a little more than one-fifth the length of the mandible. The same relative proportion is found in the Atlantic City specimen, but, as the latter is a younger individual, one would expect the symphysis to be shorter. The figure of Van Beneden and Gervais gives the impression that in the type the end of the mandible is broken, and that, hence, the symphysis is shorter than it was originally. It will be observed that figures 2 and 2a do not agree as regards the length between the tooth and the end of the jaw, figure 2a showing a greater length. In figure 2, however, the jaw seems rather too long for the cranium, and if the greater length of the symphysis shown in figure 2a were introduced, it would certainly be so. The explanation of this discrepancy is not readily found; but one may be allowed to think that the symphysis is not so blunt in the type as is shown in figure 2.

In the Atlantic City specimen the superior lateral free margin of the symphysis is straight, while in the type it is much elevated. This is no doubt due to difference in age and possibly in sex. The type shows three or four mental foramina, while the Atlantic City specimen has one large posterior one and seven smaller ones anterior to it.

Another peculiarity of the latter specimen is that the coronoid process is situated much in advance of the condyle, while the angle extends considerably behind it. In the type both are nearly in line with the condyle. I am unable to explain this difference.

In the Atlantic City specimen the axis of the tooth where it emerges from the alveolus is 91 mm. from the end of the jaw. The portion of the tooth above the alveolus is 11 mm. long at the base and 12 mm. high. It is conical and sharp pointed, and is inclined forward and a little outward, especially at the tip. At the alveolus the transverse breadth of the tooth is 5 mm. The much larger tooth in the type indicates that that specimen was a male.

The mandible of the Atlantic City specimen of M. europæus differs from that of M. bidens in the relative shortness of the symphysis, the large number of mental foramina, the more anterior position of the tooth, and the direction of the crown, which is forward instead of backward.

Dimensions of the type and two other skulls of Mesoplodon europæus.

Column headings: A: English Channel, type,^a adult. B: North Long Branch, New Jersey, female, adult. C: Atlantic City, New Jersey, 23346 U.S.N.M., male, young.

^a Dimensions taken from Van Beneden and Gervais’ figures. ^b Beak lacking. Length from occipital condyles to base of beak (straight), 312 mm. ^c Pterygoids broken. ^d At middle. ^e Estimated. One zygoma is broken. ^f Least.

VERTEBRÆ.

The vertebral formula of three specimens of M. bidens and of the Atlantic City specimen of M. europæus is as follows:

Although the skeleton of M. europæus appears from the foregoing formula to include one less thoracic vertebra than those of M. bidens, as the last pair of ribs present is as long as the preceding ones, an additional pair probably existed originally. The formula for europæus would then be: C. 7, Th. 10, L. 10, Ca. 20 = 47. ([Pl. 13], fig. 1.)

In the Atlantic City specimen all the epiphyses are free. The atlas and axis are anchylosed together, the third cervical is united to the axis by the centrum, and on the right side by the top of the neural arch; on the left side the arch is imperfect and free. The fourth to the seventh cervicals, inclusive, are all free. The arch is incomplete above in the fourth, fifth, and sixth, but complete in the seventh. There is a short neural spine on both sixth and seventh cervicals. The atlas has a broad, obliquely-truncated inferior lateral process, but no superior process, while the axis has both inferior and superior processes. The inferior process is twice as long as the superior process, and both are directed backward. They do not meet to form a ring. The third to the sixth cervicals, inclusive, have inferior processes only, that on the third being long and thin (but developed on the left side only). On the fourth and fifth cervicals the processes are short and small; on the sixth, long and broad, and directed downward. The centrum of the seventh cervical has a broad facet on the side, where the first rib is attached, and an inferior lateral process thicker than that of the sixth cervical, but also directed downward.

It is doubtful whether the foregoing characters of the cervical vertebræ are of any systematic importance, as there is a very large amount of individual variation among these animals in the development of the transverse processes and other details of structure. M. bidens, however, appears to have superior transverse processes on most of the cervicals which sometimes unite with the inferior processes to form foramina. In the specimen of M. europæus under consideration there are no superior processes, except on the axis.

Metapophyses are first distinguishable on the diapophyses of the fourth thoracic vertebra, and on the seventh assume the form of conical tubercles. On the eighth and following vertebræ they are flat, and are last distinguishable on the seventh caudal vertebra. Facets for the articulation of the tubercles of the ribs occur on the diapophyses of the first to the seventh thoracic vertebræ. On the latter vertebra the first transverse process appears as a short projection on the side of the centrum. On the eighth thoracic vertebra, the transverse process is broad and flat, with the anterior margin bent upward, and is about 48 mm. long. The base of the neural arch is strongly concave externally. The transverse process of the ninth thoracic vertebra is similar to the preceding one, but broader and not bent upward anteriorly. The base of the neural arch is also concave in this vertebra. The ends of the transverse processes of the eighth and ninth vertebræ are emarginate for the articulation of the ribs. A median inferior ridge is first distinguishable on the seventh thoracic vertebra.

As far as can be learned from the descriptions of Turner, Grieg, and others, the thoracic vertebræ of europæus do not present any marked differences from those of bidens.

The transverse processes of the lumbar vertebræ are short, broad, and flat, and somewhat curved forward. They are expanded and rounded at the free ends. The centra increase in length posteriorly, the last lumbar having the greatest length of any vertebra in the column. The neural spines increase in length from the first lumbar to the fourth, those on the remaining lumbars being subequal, but the spine on the ninth lumbar is a little longer than the others. Median inferior ridges occur on all the lumbars and are strongest at the middle of the series. The height of the centrum of the ninth lumbar is 63 mm., width 73, and length 116. The highest neural spine is 233.

As above mentioned, the first of the vertebræ counted among the lumbars may be the last thoracic vertebra, but as there is no indication of an articular facet at the end of the transverse process it is not so considered in this place.

The lumbar vertebræ in M. bidens appears to be more nearly equal in length than in the present species, but are not different otherwise.

The spines of the caudal vertebræ decrease rapidly in height posteriorly, and disappear after the tenth caudal. The transverse processes resemble those of the lumbars, but are shorter. They are last distinguishable on the eighth caudal. The transverse process of the seventh caudal is perforated by a vertical foramen. Similar but much smaller foramina occur on the sides of the centra of the eighth and ninth caudals. In these vertebræ the inferior ridges are also pierced by foramina. In the fourth caudal a ridge appears on the side of the neural arch on a level with the top of the centrum, and similar ridges are found on the succeeding vertebræ as far as the ninth caudal. The last ten vertebræ are without processes or neural arches.

Sir William Turner states that the caudals of M. bidens are without vertical foramina, but the figure in Van Beneden and Gervais’ Osteography (plate 22) shows them in the same position as in M. europæus. The inferior ridges, however, appear to be imperforate in the former species.

RIBS.

The first seven pairs of ribs have both tubercle and head. The first is nearly as long as the second, and is very broad at the proximal end. In the seventh pair the head is double, one facet of the rib articulating with the facet on the posterior margin of the centrum of the sixth thoracic vertebra and the other with the short transverse process on the side of the centrum of the seventh thoracic vertebra. The eighth and ninth pairs of ribs articulate only with the transverse processes of the eighth and ninth thoracic vertebræ, respectively. The ninth pair of ribs, as already stated, is nearly or quite as long as the eighth, from which it seems probable that a tenth short pair was present originally. There is, however, no trace of a facet for the articulation of such a rib on the end of the transverse process of what appears to be the first lumbar vertebra.

The only difference between the ribs of M. europæus and those of M. bidens appears to be that the first pair is much longer proportionately in the former species.

STERNUM.

The sternum presents no differences of importance from that of M. bidens figured by Grieg,[24] except that the fourth and fifth segments are anchylosed together, both laterally and transversely, and that the two sides are symmetrical. ([Pl. 13], fig. 2.)

PECTORAL LIMB.

The scapula of M. europæus presents an entirely different appearance from that of M. bidens as figured in Van Beneden and Gervais’ Osteography (plate 22). In europæus the scapula is very high anteriorly, the anterior border is convex forward and the anterior crest convex backward, bounding an elongated elliptical area. The posterior margin is straight. The acromion is short, with convex margins at the base, beyond which it narrows suddenly and terminates in a straight, cylindrical process, which is strongly inclined upward. The coracoid is as long as the acromion, nearly straight and horizontal, but expanded at the end. ([Pl. 13], figs. 3, 4.)

The phalangeal formula of the Atlantic City specimen of M. europæus and those of three Norwegian specimens of M. bidens are as follows (the metacarpals being included):

Phalangeal formula of M. europæus and bidens.

In M. europæus the metacarpal of the third digit is much constricted in the middle. The shaft of the ulna is straight. Except in these particulars and the relatively small size of the whole pectoral limb, the latter appears not to differ materially from that of M. bidens. As shown above, the first digit in M. bidens consists of the metacarpal bone only, while in M. europæus a phalange is also present.

Dimensions of the skeleton of the Atlantic City specimen of M. europæus, No. 23846, U.S.N.M.

^a Placed in contact. ^b From the inside, without the cartilaginous tip.

HISTORY OF THE ATLANTIC CITY SPECIMEN.

Regarding the finding of the Atlantic City specimen and its exterior and gross anatomy, nothing has been published except brief references by Sir William Turner in 1889[25] and Dr. Glover M. Allen in 1906,[26] taken from a newspaper report of a communication made by myself before the Biological Society of Washington in 1889. On that account a somewhat detailed statement regarding it will be made in this place.

This individual ([Pl. 41], figs. 1, 2) was a male, 12½ feet long. It was observed by the crew of life-saving station No. 28, near Atlantic City, New Jersey, on the afternoon of March 28, 1889. It had come inside the bar which skirts the coast at this point, and was apparently unable to find its way out. It was captured with some difficulty, after being wounded in the throat, and was dragged up on the beach near the station. Later in the day it was carried to the skating rink of Messrs. Johnson & McShea, at Atlantic City, where it was exhibited until Monday, April 1. On the next morning it was sent by express to Washington.

I examined it for the first time in Atlantic City on March 29. It was then lying on the floor of the skating rink in such a position that the under surfaces were concealed, and, as the teeth were not visible, I mistook it for a female. Upon its arrival in Washington, however, where it could be examined under more favorable circumstances, it proved to be a male. The following measurements were taken from the fresh specimen:

External dimensions of a specimen of M. europæus from Atlantic City, New Jersey.

EXTERNAL FORM AND COLOR.

The general form was slender and elongate. The beak sloped gradually from its extremity to the forehead, and there was no constriction separating the beak from the remainder of the head. Behind the blowhole, the outline of the back commenced at a higher level, but immediately curved slightly downward, indicating the position of the neck. The line then rose gradually until the anterior base of the dorsal fin was reached. Behind the fin the outline sloped downward gradually to the flukes.

The dorsal fin was relatively small, falcate, and obtusely terminated. The distance in front of its anterior base was three-fifths of the total length. Its posterior margin was continuous with the ridge of the back, which extended to the flukes and terminated abruptly a little anterior to the middle point of the antero-posterior breadth of the flukes. In front of the fin the back was rounded.

The pectoral fins were small and were placed low down on the sides. Their anterior base was as far removed from the eye (in a straight line) as the eye was from the extremity of the beak. Their shape was somewhat different from that of the flippers of M. bidens figured by Sir William Turner.[27] Their anterior margin was nearly straight throughout; the extremity was evenly and distinctly rounded off. The posterior margin was slightly convex in the distal half and straight proximally.

The conformation of the region of the axilla was quite peculiar. The hard integument of the posterior margin of the flipper was continued proximally inward and forward to a point near the head of the humerus. The triangular area between this stiff edge and the side of the body was occupied by a thin, soft, wrinkled skin, in the middle of which the olecranon could be felt. On the side of the body this soft integument occupied an area nearly as large as the flipper, the underlying thick layer of blubber ending abruptly, especially below. A depression was thus formed in which the flippers could be placed so as to be almost in the same general plane with surrounding surfaces of the body. They are probably so placed when the animal is swimming.

The flukes had the general lunate form common to all species of the order. The posterior margin is not divided in the center. Its middle third was convex; its lateral thirds concave. In these and other respects the shape of the flukes agreed closely with Sir William Turner’s excellent figure of M. bidens.[28] The antero-posterior breadth of the flukes was, however, somewhat greater in proportion to their transverse breadth than is indicated in this figure. The caudal peduncle terminated above at a point 6½ inches in front of the posterior margin of the flukes. On this margin were situated three star-shaped white scars, which appeared to mark the points of attachment of crustacean parasites.

The margins of the upper jaw were very obtuse posteriorly, the rostrum being covered with a layer of blubber of gradually increasing thickness. A depression bounded by gradually converging lines extended 4¼ inches back of the angle of the mouth.

The inferior surface of the bony palate extended below the level of the lips, and the sides of the former were visible upon looking into the mouth laterally.

The blowhole was large and somewhat unsymmetrically placed, the right angle being the more anterior. The concavity was forward.

The eye was situated a little below the line of the mouth and 20¼ inches from the extremity of the snout.

The external opening of the ear was 2⅞ inches behind the posterior angle of the eye, and a little below the line of the lower eyelid.

The two throat-furrows were of unequal length. The left furrow was 6¾ inches long, and its anterior end was distant 8⅝ inches from the extremity of the jaw. The right furrow did not extend quite so far forward, and was 7⅜ inches long.

The furrows converged posteriorly; they were separated by an interval of ⅝ inches anteriorly and 5⅛ inches posteriorly. Between the anterior ends of the main furrows was a small one, about an inch long, but it is doubtful whether this was a natural fissure. I did not observe it when the whale was in Atlantic City.

The natural color of the specimen had largely disappeared before I examined it, but Captain Gaskell and others who saw it while still fresh agreed that it was very dark slate-gray on the back, lighter on the sides, and whitish on the belly. I observed that a broad area between the pectoral fins was slate-gray, and contrasted with the white of the throat and belly. The whitish color ended somewhat abruptly and irregularly at the anus, and the flukes, as well as the pectoral and dorsal fins, were probably very dark slate-gray, or blackish, when fresh.

The epidermis was exceedingly smooth and glossy throughout.

The tongue was purplish-white. The roof of the mouth was black, except at the posterior end, where there was an irregular area of pinkish-white.

The integument of the roof of the mouth was smooth and shining. Its surface was convex at the extremity of the beak, but the central portion was concave, while at the posterior end it was again raised into a rounded pad. In these respects the shape of the integuments coincided with that of the underlying maxillæ, upon which they were closely fitted. The sides were rounded, and a shallow groove intervened between them and the lips. This groove was continued around the roof of the mouth behind, and formed a demarcation between this part and the œsophagus.

The tip of the tongue was 7½ inches from the extremity of the jaw. It was oval in outline, the extremity is obtuse, and it was entirely bound down. The margin was entire, and not crenulate, as in many dolphins.

Dorsal and ventral views of the stomach are shown in [Pl. 40], figs. 1 and 2; a dorsal view of the lungs in [Pl. 13], fig. 5; and of the perineum in [Pl. 40], fig. 3. A description of the gross anatomy is reserved for a subsequent paper.

The external dimensions of the Atlantic City specimen of M. europæus are given in the following table, together with those of nine European specimens of M. bidens taken from various authors, and assembled here for purposes of comparison. The dimensions of the Annisquam specimen which, as already explained ([p. 9]), represents a third species, are also added.

External dimensions of Mesoplodon europæus, M. bidens, and M. densirostris.

Column headings: M. europæus. C: Atlantic City, 1889, U.S.N.M. male, imm. M. bidens. D: Brodie House, Scotland, 1800, (Sowerby), male, adult.[a] E: Overstrand, England, 1892, (Southwell), female, adult. F: Dalgety, Scotland, 1888, (Turner), male. G: Hillville, Kerry, Ireland, 1864, (Andrews), male (?). H: Hevringholm, Denmark, 1880, (Reinhardt), female, adult. I: Rugsund, Norway, 1901, (Grieg), male, adult. J: Saltö, Sweden, 1885, (Aurivillius), male, young. K: Landenæs, Norway, 1895, (Grieg), male. L: Ostend, Belgium, 1835, (Dumortier), female, young. M. densirostris? M: Annisquam, Mass., 1898, (Allen), female.

^a Type-specimen. ^b Straight. ^c To center of blowhole. ^d From tip of upper jaw (curvilinear). ^e Curvilinear. ^f Left. The right=192^mm. ^g Along center. Along anterior border = 292^mm±. ^h Along anterior border. ⁱ Straight; point of measurement not given. ^j Along side. ^k From anterior base, unless otherwise indicated.

Since the foregoing account of europæus was written, a description of the type-skull, with two excellent photographic figures, has been published by L. Brasil,[29] of the Caën Museum. A comparison of the figures with those of the Atlantic City and Long Branch skulls on Pls. [2] and [8] of the present article, confirms the identification of the latter specimens with M. europæus. Besides a brief description of the type-skull M. Brasil’s paper contains measurements and two text figures of the right mandibular tooth, natural size.

MESOPLODON STEJNEGERI True.

Mesoplodon stejnegeri True, Proc. U. S. Nat. Mus., vol. 8, p. 584. Oct. 19, 1885.

This species was originally described from a single cranium of a young individual, which was collected by Dr. L. Stejneger on Bering Island, Commander Group, Bering Sea, in 1883. With but a single skull, the characters of the species could not be very satisfactorily defined, and some European cetologists have been inclined to doubt its validity.[30] In 1904, however, another skull was obtained by the National Museum, which made it certain that the species was entirely distinct from M. bidens or other known forms of the genus. Early in the year mentioned Dr. D. S. Jordan, president of Stanford University, called my attention to a small whale, which stranded on the coast of Oregon, 1½ miles south of the United States life-saving station on South Beach, Yaquina Bay, near Newport, in February, and proved later to represent the present species. Doctor Jordan’s information was obtained from Mr. J. G. Crawford, of Albany, Oregon, who wrote him in part as follows, under date of March 7, 1904:

Herewith I enclose a stereograph of a head of a member of the whale family, which I made at Yaquina Bay, Oregon. The animal was 17 feet long, with fluked tail, soft, smooth skin, blowhole on top of head, and two tusks in the mandible, but no [other] teeth in the mouth. The tusks are thin and apparently hollow. Length of head, 32 inches; width, 14 inches; height, 11 inches; blowhole, 5 inches. Eyes low on head. Width of mandible [jaw] at end: Upper, 1½ inches; lower, 1¾ inches. Width between tusks, 3 inches. The blubber was about 2 inches thick on the head. It went ashore about the 15th of February, 1½ miles south of the life-saving station on South Beach, 2½ miles south of Newport, Oregon. The head had been severed before I arrived.

A clipping from the Oregonian newspaper contains the following:

Albany, Oregon, March 2 [1904]. A peculiar specimen of the whale variety has been reported on the Oregon coast, near Newport. J. G. Crawford, of Albany, has just returned from a trip to Newport, where he made a picture of the head of the strange animal. The body was washed upon the beach during the recent storm which swept the coast. It is about 15 feet long. * * * Residents of the vicinity say they have never seen anything like it on the Oregon coast. * * * On either side of the mouth are two villainous-looking tusks several inches in length. They are at the back of the mouth, and extend up to a level with the top of the upper jaw. They are very wide and flat, squared on top. The mouth has no other teeth. * * *

The head is equipped with a blowhole, like that of a whale. The eyes are very low, almost underneath the lower jaws.

The body is in a good state of preservation, the flesh having been torn but little by the birds.

On receipt of the foregoing information, letters were immediately addressed to Mr. Crawford and also to the keeper of the life-saving station at South Beach, Capt. Otto Wellander, asking that, if possible, the entire skeleton be preserved. Captain Wellander replied that the whale had not been dead long when washed ashore; that he had tried to find the body, but that the high tides had either carried it away or buried it under driftwood.

The skull when cleaned passed into the possession of Mr. J. G. Crawford, who sent to the Museum some excellent photographs of it, and also of the head before the flesh had been removed. Later he sent the skull itself to the Museum for my examination, and finally very generously presented it to the Museum in exchange.

The skull is that of an adult individual, in nearly perfect condition, with the mandible and teeth. The parts missing are the left malar, the left tympanic bone, the distal ends of the pterygoids and the proximal ends of the premaxillæ. ([Pl. 3], fig. 2.)

SKULL.

The Oregon skull exhibits all the characters included in the original diagnosis of the species,[31] but two of these, namely, the lack of a groove in front of the premaxillary foramen, and the vertical position of the premaxillæ distally, I do not at present consider of any importance, as they are shared by M. bidens. The species, as represented by the Oregon skull, however, presents other characters which clearly differentiate it from any other species of the genius. As it is without a basirostral groove, it allies itself in that respect to M. bidens, europæus, and hectori. Unlike those species, it has the premaxillary foramen behind the maxillary foramen, and in this respect resembles densirostris and grayi. Perhaps the most salient characters in which stejnegeri differs from bidens and all other known species are the erect position and flat surface of the supraoccipital and the very prominent backward extension of the frontal plate of the maxilla. This backward extension is so great that when the beak is horizontal a vertical line through the posterior margin of the maxilla passes considerably behind the temporal fossa. The only species which approaches stejnegeri in this respect is hectori, but in the latter the supraoccipital instead of being flat above the condyles is very strongly convex.

Another very marked character of stejnegeri is that the extension of the lateral free margin of the orbital plate of the frontal, anterior to the orbit, is equal to the length of the orbit itself. In bidens and all other known species this extension is only from one-third to one-half the length of the orbit. Numerous other distinguishing characters will be mentioned in the course of the following description of stejnegeri, which is drawn from the adult Oregon skull, but modified when necessary by reference to the type skull from Bering Island. Comparisons are made chiefly with M. bidens, which is on the whole the best known species.

In the Oregon skull of stejnegeri, the breadth between the post-orbital processes does not exceed the length from the occipital condyles to the maxillary notches. The skull is, therefore, narrower in proportion to its length than in any other species of the genus except hectori, as represented by the skull figured by Flower. This skull was, however, that of a young individual. It is probable that in adults of this species the skull is broader than in stejnegeri.

In the latter species, again, the length of the brain-case, between the occipital condyles and the maxillary notches, is just equal to the distance from the latter point to the distal end of the maxillæ, and the rostrum, including the premaxillæ, is much shorter than in other species of Mesoplodon, except hectori, as represented by the young skull above mentioned.

The foramen magnum is very small, being less in width than the condyle on either side of it. In this respect it differs widely from bidens and other species (as far as can be ascertained from the figures available), except europæus, in which the relative size is about the same.

The supraoccipital rises vertically above each condyle to the very top of the skull, being neither convex nor strongly bent forward as in other species, and especially bidens. In the median line, however, while the occipital bone is flat immediately above the foramen magnum, it is deeply concave higher up and without a median ridge. The outline of the occipital crest, viewed from behind, is semicircular. In all the foregoing characters the occipital region differs widely from that of bidens and other species. The only close resemblance is found in the old skull of europæus from Long Branch, New Jersey, and even here the sides of the occipital above are far less prominent, their outline is much more convex, the occipital crest is angular, and the median depression is less pronounced.

Dorsal aspect ([Pl. 3], figs. 1, 2).—The most noticeable feature of the upper surface of the skull is the large backward extension of the frontal plates of the maxillæ, the free margins of which converge strongly. The outline of the anteorbital region is rounded. The anteorbital notch is a shallow emargination. Anterior to this is a second still shallower emargination, the “pseudo-notch.” The margin between the two is much thickened, but does not form a distinct projection or tubercle, as in bidens and other species. The superior orifices of the nares are unsymmetrical as regards position, the left being somewhat in advance of the right. The maxillæ are concave around the maxillary foramen, and external to this foramen is an elongated ridge about as in europæus. The rostral portion of the maxillæ is broad at the base but tapers more rapidly than in bidens. The margin is thick. At the middle of the beak the outline of the maxillæ at a lower level is visible from above, which is not the case in bidens or europæus. The rostral portion of the premaxillæ is oblique proximally and vertical distally. Unlike bidens, these edges are sharp throughout. The mesethmoid ends opposite the maxillary foramina. Anterior to it is seen the concave upper surface of the vomer, which, however, becomes flat distally. At about the middle of the beak the anterior end is clasped by the posterior forked end of a “mesirostral” ossification, which has a convex surface. This ossification begins proximally below the edges of the premaxillæ, but its surface rises gradually anteriorly, and at the end of the beak it is much above the premaxillæ. The end of the beak consists of the consolidated mass of the premaxillæ and mesirostral ossification, the whole being convex above and below, but flat on the sides. The ossification has a deep median groove, which reaches to within 95 mm. of the tip of the beak.

It will be seen that the conformation of the upper surface of the beak is quite different from that of bidens or any other species.

The maxillary foramina are large and directed forward, and have a distinct broad channel in front of them. In the Oregon skull the right foramen is single, but the left divided into two. The premaxillary foramina are a little behind the maxillary foramina. The distance between the maxillary foramina is less than that from the median line to the anteorbital notch. In bidens it is much greater.

Lateral aspect ([Pl. 9], figs. 1, 2).—A most noteworthy feature of the skull when viewed from the side is the great length between the orbit and the maxillary notch, which far exceeds that found in bidens and other species, being equal to the length of the orbit itself. The latter is about as long as the temporal fossa, which is somewhat flattened above, as in europæus. The outline of the supraoccipital is straight and nearly vertical. The zygomatic is more massive even than europæus and is especially thick below. The inferior outline of the beak is convex proximally as in europæus and layardi. There is no basirostral groove, the edges of the maxillæ being very thick in front of the maxillary notch. Over the orbit the maxillæ are thick and beveled, but not raised as in bowdoini.

Ventral aspect ([Pl. 6], figs. 1, 2).—The beak is convex in the proximal half, much as in europæus, but farther forward is concave, except in the median line, where there is a narrow ridge formed proximally by the vomer, which in the type skull appears as a narrow lozenge 60 mm. long. In the adult Oregon skull it is anchylosed with the premaxillæ. The maxillæ extend to within 107 mm. of the end of the beak. The under surface of the beak is much more like that of europæus than of bidens.

A narrow strip of the palatines extends around the base of the pterygoids in front, but the two strips do not meet in the median line. In the type-skull they do not extend inside the pterygoids. The expanded anterior end of the malar is very long and also forms the bottom of the maxillary notch, which is the case in europæus but not in bidens. The inferior borders of the pterygoids are convex anteriorly, as in europæus, and are continued laterally, so that the sinus is deep as in that species. The lachrymal is very long, the free margin having a length of 55 mm. The posterior margin of the zygomatic process is concave, rather than convex as in bidens.

The tympanic bulla does not differ materially from that of bidens in size or shape, as far as can be judged from the figures given in Van Beneden and Gervais’ Osteography (plate 26, figs. 4, 4a). The periotic is similar in size to the same bone in bidens, but the posterior end is more narrowly pointed and the anterior end is much lower, relatively. In europæus, as far as can be determined from the material at hand, the form and size of the earbone is similar to that of stejnegeri, but in the latter the anterior margin of the tympanic bulla is more nearly transverse and the posterior inferior groove is curved. ([Pl. 35], fig. 2.)

In the Annisquam skull, supposed to represent densirostris, although from a young individual, the earbone is very much larger, especially the periotic, which is also quite differently shaped.

MANDIBLE.

The mandible of stejnegeri is much broken in the region of the angle on both sides, but otherwise complete. As compared with a mandible of an adult bidens, the most conspicuous differences are the shortness of the symphysis, the sharp upward bend of the inferior margin anteriorly, and the large size of the alveolus. The symphysis in the adult Oregon specimen of stejnegeri is 140 mm. long, or scarcely more than in the young specimen of europæus from New Jersey, and exactly the same as in the adult type-specimen of the latter species, as figured by Van Beneden and Gervais. The alveolus lies entirely behind the symphysis, its anterior end being 160 mm. from the anterior end of the jaw. It is 113 mm. long and 18 mm. wide. The mandible is 62 mm. high at its middle point. The coronoid process is more anteriorly situated than in bidens and the portion of the posterior margin of the ramus which remains indicates that the angle was strongly directed backward. ([Pl. 11], fig. 4; [pl. 12], fig. 1.)

TEETH.

The teeth are remarkable for their size and form. They are somewhat more than twice as broad as teeth of adult males of bidens, as shown by the figures of Lankester[32] and Grieg,[33] and also a little longer. They are, in fact, probably broader than, or at least as broad as, the teeth of any other species of Mesoplodon, not excepting layardi. Sir William Turner remarks regarding a specimen of layardi examined by him that “the breadth of the tooth, where it emerged from the alveolus, was 3½ inches.”[34] He does not state, however, whether the measurement was taken along the top of the alveolus, at an angle with the transverse axis of the tooth, or along the transverse axis itself. At all events, the teeth figured by Owen and others are much less than 3½ inches broad. The teeth of adult europæus are only 2 inches broad, and of bidens, as already stated, 1½ inches broad.

In stejnegeri ([Pl. 12], figs. 1-3) the portion of the tooth above the alveolus is inclined slightly inward and backward, but the pointed tip curves outward so as to be vertical. When extracted from the alveolus, the whole tooth is found to be concave internally and convex externally. The posterior margin is convex and the anterior sinuous, a slight convexity occurring on the portion which projects above the alveolus. In this place the outer coating of cement is broken through, showing the underlying dentine or osteo-dentine, which is somewhat corroded or absorbed. This is particularly noticeable on the left tooth.

The upper margin of the tooth is transverse, or nearly at right angles with the anterior and posterior margins. The posterior angle is rounded and the anterior raised into an acute point by the projection of the dentine as a distinct, sharp cusp. The inferior end of the tooth is cut off obliquely and the margin is broken by numerous prominent rugosities. The surface of all that part of the tooth which is contained in the alveolus and covered by the gum above it is rugose, while the part above the gum is quite smooth and highly polished.

The right tooth has the following dimensions (in straight lines): Length of anterior border, 150 mm.; length of posterior border, 107; length of superior border, 54; length of inferior border, 86; average length of exposed dentine tip, 10; greatest breadth of tooth, antero-posteriorly, 81; greatest breadth of tooth, transversely, 15; distance from center of base of exposed portion, when in position in the alveolus, to tip of dentine projection, 82; distance from center of base of portion above the gum to tip of dentine projection, 70; distance from center of base of portion above the gum to center of inferior margin, 76.

The dimensions of the skulls are as follows, those of the type-specimen having been revised and corrected:

Dimensions of two skulls of M. stejnegeri.

Column headings: A: 143132 U.S.N.M. Yaquina Bay, Oregon, adult. B: 21112 U.S.N.M. Bering Id. Type (1715), young.

^a Tip of rostrum lacking. ^b The skull is much worn around the left notch and the measurement is only approximate.

EXTERNAL FORM.

The photograph of the head ([Pl. 40], fig. 4) shows that the end of the beak was quite blunt, and the lower jaw quite a little longer than the upper. The superior margin of the lower jaw, which is concave in front of the tooth, is strongly convex and elevated at the side of it and behind it. The inferior margin of the upper jaw is straight anteriorly, but farther back appears to be pressed upward by the tooth. An examination of the skull shows that the mandible can be lowered so that the teeth are below the upper jaw, but when so lowered the space between the teeth and the upper jaw on each side is barely a quarter of an inch (6 mm.). With the integuments in place, it is doubtful whether the mouth could be opened any wider than is shown in the photograph. The convexity of the head, shape of the blowhole, position of the eye, etc., do not appear to differ materially from the same characters in adults of M. bidens.

Genus ZIPHIUS Cuvier.

ZIPHIUS CAVIROSTRIS Cuvier.

Ziphius cavirostris Cuvier, Oss. foss., 2d ed., vol. 5, 1823, p. 353. Hyperoödon gervaisii Duvernoy, Ann. Sci. Nat., ser. 3, Zoöl., vol. 5, 1851, p. 49. Ziphius gervaisii Fischer, Nouv. Arch. Mus. Paris, vol. 3, 1867, p. 55. Hyperoödon semi-junctus Cope, Proc. Acad. Nat. Sci. Phila., 1865, p. 15. Ziphius semijunctus True, Proc. U. S. Nat. Mus., vol. 8, 1886, p. 586. Ziphius grebnitzkii Stejneger, Proc. U. S. Nat. Mus., vol. 6, 1883, p. 77.

It has not seemed to me necessary in the present connection to attempt to cite all the multitudinous names which have been given to this species, especially as those zoologists most competent to judge, including Van Beneden, Flower, and Turner, after detailed consideration, have concluded that but one species of Ziphius, or at most two species, exist at present.[35]

Nearly all the skulls in European museums are assigned by the zoologists mentioned to Z. cavirostris proper, but some doubt has been entertained regarding two or three European skulls, and one specimen from Argentina, described by Burmeister. These last-mentioned specimens have been thought to possibly represent a second species, Z. gervaisii. The principal characters of the latter are the narrow, flat premaxillæ, the lack of a prominent mesirostral ossification, and small teeth. From the large series of skulls in the National Museum, I am able to dispose of the doubt concerning Z. gervaisii. I find that wherever the characters above mentioned occur the sex (when known) is female. There is every reason, therefore, to believe that Z. gervaisii is the female of Z. cavirostris.[36] I will return to this point again later.

In 1865 Cope described a species from Charleston, South Carolina, under the name of Hyperoödon semijunctus. In 1886 I referred it to the genus Ziphius, but was in doubt as to its specific identity. I thought that it might represent Z. gervaisii, which is interesting in the present connection because the type-specimen was a female.

In 1883 Dr. L. Stejneger described a species which he had discovered on Bering Island, Bering Sea, under the name of Z. grebnitzkii. Through the instrumentality of Doctor Stejneger and Governor Grebnitzki, the National Museum later received a large series of skulls from the same locality. The question of whether this species is identical with Z. cavirostris, or distinct, has caused me much study, and forms the principal subject of this chapter.

The National Museum has at present the following material, which may be considered as certainly representing Z. cavirostris:

1. A complete skeleton and cast of an adult female, 19 feet 4 inches long, obtained at Barnegat City, New Jersey, October 3, 1883. Cat. No. 20971.

2. A complete skeleton and photographs of an adult male, 20 feet 1 inch long, obtained at Newport, Rhode Island, in 1901, through Dr. E. A. Mearns, Mr. L. di Z. Mearns, and Capt. Gus Soderman. Cat. No. 49599.

3. The collection contains also the skeleton of the young female individual obtained at Charleston, South Carolina, prior to 1865, which constitutes the type of Hyperoödon semijunctus Cope. It was originally in the Charleston College Museum, but later was received by the National Museum in exchange. This individual was between 12 and 13 feet long. Cat. No. 21975.

In addition, the national collections contain the following material, known to, or supposed to, represent the species Z. grebnitzkii:

4. Cat. No. 20993. Skull of a male (?).[37] Collected by Dr. L. Stejneger in Bering Island, 1882. Orig. No. 1521. Type of Ziphius grebnitzkii.

5. Cat. No. 21245. Skull. Orig. No. 1758.

6. Cat. No. 21246. Skull. Orig. No. 2531.

7. Cat. No. 21247. Skull. Orig. No. 1849.

8. Cat. No. 21248. Skull of a male (?).

9. Cat. No. 83991. Skull.

The five skulls preceding were also collected by Doctor Stejneger in Bering Island in 1882 and 1883.

10. Cat. No. 22069. Skull of a female (?).[37]

11. Cat. No. 22874. Skull.

12. Cat. No. 22875. Bones of an immature individual.

These three specimens were collected and presented by N. Grebnitzki.

13. Cat. No. 142579. A series of photographs of an individual captured in Kiska Harbor, Alaska, September, 1904. Presented by Dr. J. Hobart Egbert.

14. Cat. No. 84906. Photograph of the skeleton of an individual washed ashore at St. Simon Island, Georgia, in 1893, and belonging to Mr. W. Arnold.

In the genus Ziphius, as in other ziphioid genera, a study of the characters of the skull appears to afford the best basis for discrimination of species. We have first to consider whether the North American species is the same as the European and New Zealand species, and afterwards whether the North Pacific species is identical with or distinct from these.

The published measurements of specimens from the coasts of Europe and New Zealand, currently believed to represent the single species Z. cavirostris, are rather meager, and, furthermore, prove, on examination, to present so little uniformity that they are of limited use for comparison with measurements of skulls from the Atlantic coast of the United States. About all that can be said is that the latter skulls are of about the same size as the former and that the proportions do not present any striking differences. For detailed measurements of the American skulls, see [page 53].

On account of the uncertainty as regards the measurements, I have had recourse to the published descriptions and figures, especially those of Van Beneden, Sir William Turner, and Doctor Haast. So far as I can perceive, there is nothing in these descriptions that is not applicable to the skulls Nos. 49599 and 20971, from Newport, Rhode Island, and Barnegat City, New Jersey, respectively, in the National Museum, and I can find no reason for regarding the latter other than as representatives of Z. cavirostris.

HISTORY OF THE NEWPORT, RHODE ISLAND, SPECIMEN.

Of the Newport specimen, No. 49599, the Museum has the complete skeleton, together with external measurements and a photograph. From data at hand it appears that the animal was originally obtained in Narragansett Bay about October 30, 1901, and afterwards towed to Fort Adams, near Newport. A few days later it was sent adrift again and stranded in the harbor of Dutch Island, near Canonicut Island, which is opposite Newport. While at Fort Adams its existence was made known to the Museum by Dr. E. A. Mearns, U. S. Army, and his son, Louis Mearns; and a preparator was sent to obtain the skeleton. With the aid of Captain Soderman, of the government tug Monroe, he found it at Dutch Island, and reported that it was a male, 20 feet 1 inch in length, measured along the curves of the back (18 feet 6 inches in a straight line). The epidermis was nearly all lacking, but the back appeared to have been black. The length in a straight line, as reported by Mr. Louis Mearns, was 19 feet. The complete measurements taken by the preparator, Mr. J. W. Scollick, are as follows:

External dimensions of Ziphius cavirostris, male, Cat. No. 49599, U.S.N.M., Newport, Rhode Island.

The breadth of the pectoral fin, as shown by the skeleton, was 5¾ inches.

The photograph, which is reproduced in [Pl. 41], fig. 4, gives a good idea of the general form of the animal.

HISTORY OF THE BARNEGAT CITY, NEW JERSEY, SPECIMEN.

Of the Barnegat City specimen, No. 20971, the Museum has the complete skeleton, together with a cast of one-half of the entire animal, and another of the head, and some measurements, all of which were obtained by Mr. William Palmer and myself October 3, 1883. The Museum received notice of the stranding of this specimen from Capt. J. H. Ridgway, of the United States life-saving station at Barnegat City. It was an adult female, 19 feet 4 inches long in a straight line. The complete measurements, taken in straight lines with a rod and cord, are as follows:

External dimensions of Ziphius cavirostris, female, Cat. No. 20971, U.S.N.M., Barnegat City, New Jersey.
(Measured in straight lines with rope and bar.)

I neglected to make a full description of the color, but noted that it was stone gray, lighter above and darker below; snout nearly white. The cast, which was painted from a sketch made at Barnegat City and from pieces of skin brought to Washington, bears out this note in general, but with modifications. The color of the body as a whole is gray tinged with dull yellowish. The gray is darker on the back than on the belly, but on the latter is a large area of dark brown, reaching from near the pectoral fins to and beyond the anus, and halfway up on the sides. On this dark area are several large oval whitish blotches, some two inches in diameter. Both upper and lower jaws nearly to the angle of the mouth are cream white. On the sides and belly the gray color is speckled with black spots of about the size of a grain of wheat. The pectoral fins are dark gray above and below; the flukes were similarly colored.

A comparison of the dimensions of the two specimens above described with those of European and New Zealand specimens is afforded by the following table (the measurements being reduced to percentages of the total length):

External dimensions of Ziphius cavirostris. (Reduced to percentages of the total length.)

Column Headings: A: Newport, Rhode Island 49599 U.S.N.M., male, 1901. B: Barnegat City, New Jersey, 20971 U.S.N.M., female, 1883. C: New Brighton, New Zealand, female. D: Punta, Corsica, 1842. E: Buenos Ayres, Argentina, male, 1865.

^a Curvilinear. ^b Straight. ^c To anterior base. ^d Lower jaw to “beginning of pectoral.” ^e From tip of upper jaw. ^f From tip of lower jaw. ^g Points of measurements not specified. ^h From the bones; from outer anterior margin of proximal expansion of ulna. ⁱ Along center. ^j From the bones. The external measurement originally taken by Scollick is entirely too large. ^k The skull gives this measurement as 10.4 per cent. The original measurement by Scollick is entirely too large and can not be correct. The same is probably true regarding length to blowhole, but I can not prove it.

The close correspondence in proportions shown in this table favors the idea of specific identity, and taken with the similarity in size, and characters of the skull, warrants, I think, the assumption that the specimens from the Atlantic coast of the United States belong to Z. cavirostris.

COLORATION.

It should be remarked, however, that the Barnegat City specimen does not agree in color with any of the European or New Zealand specimens. On the other hand, the latter show a most extraordinary diversity in color, some being black, with the head and back as far as the dorsal fin white; others all black above, white below, and the head black and brown. The color of the young specimen from Buenos Ayres, Argentina, is described by Burmeister as follows:

All the body of the animal is of a light gray color, a little yellowish, resembling the color of light ash, but much darker on the back and much lighter on the belly. The fins are much darker than the back—almost black—and the large fin of the tail has a very pure white area of irregular shape on the underside.

If the indications from the skull and proportions are trustworthy Z. cavirostris must be a species in which the color is very variable, differing perhaps in the two sexes, or with differences in age. This is, however, by no means certain at present, and whether the diversities of color reported in different specimens are merely individual variations, or are due to post-mortem changes, remains to be discovered. It will be noticed that the color of the Argentine specimen is nearest to that of the Barnegat City specimen.

TYPE OF ZIPHIUS SEMIJUNCTUS (COPE).

The type-specimen of Ziphius semijunctus (Cope), as already mentioned, is a young female.[38] The most noticeable characters which it presents are that the premaxillæ are flat proximally, and that the teeth are small, sharp-pointed and open at the roots. The form of the teeth is undoubtedly due to immaturity, but as the shape of the premaxillæ is similar to that found in the nominal species gervaisii, it might be thought necessary to refer semijunctus to the latter species. As will be shown later, however, this form of the premaxillæ appears to be characteristic of the adult female of cavirostris, and of immature individuals of either sex, the young, as in many kinds of animals, resembling the adult female rather than the male.

I have been able to find but one character in the skull of semijunctus which might be regarded as specific. This is that the lachrymal bone is thick distally, and cut off square at the end. In other specimens of Ziphius examined it is thin and flat, and rounded or pointed at the end. As there is much individual variation in the form of the lachrymal, this peculiarity alone is, in my opinion, an insufficient indication of the validity of the species.

COMPARISON OF SKELETONS.

A comparison of the skeletons of the three individuals from the Atlantic coast of the United States reveals a number of differences of more or less importance. Were it not for the lack of reliable differences in the skulls, it might be considered that these variations in other parts of the skeletons indicated specific difference. I am disposed, however, since the Barnegat and Newport specimens are of opposite sexes, to regard them partly as sexual and partly as individual. In the case of the Charleston specimen (semijunctus), the skeleton, besides being immature, has been very much damaged by careless handling, and nearly all the bones are somewhat abraded. It is, therefore, only available to a limited extent for purposes of comparison. As no description of a Ziphius skeleton from the coast of the United States has, so far as I am aware, been published hitherto, and as descriptions of skeletons of Old World specimens are few and rather brief, I shall give below a detailed comparative description of the American specimens. For the sake of brevity, I shall refer to each specimen merely by the locality.

VERTEBRAL COLUMN AS A WHOLE.

The vertebral formula in the three North American specimens and in four Old World specimens and Burmeister’s Argentine specimen is as follows:

Vertebral formula of Ziphius cavirostris.

In the figures of the Argentine specimen the last ten caudals are practically without characters, and it is perhaps allowable to question whether the terminal two or three were not added to make an even taper to the end of the column. If such be not the case, this specimen had more vertebræ than any other.

CHARACTERS OF THE VERTEBRÆ.

Newport (male).—The seventh cervical vertebra presents a conical metapophysis, which on the first thoracic vertebra forms of a rather thick, long, declining process ending in a facet for the tubercle of the first rib. This metapophysis maintains nearly the same form as far as the sixth thoracic vertebra, but on the third thoracic a mammiliform process makes its appearance on the anterior margin near the tip, and becomes more prominent on each succeeding vertebra. On the seventh thoracic it becomes larger, thin, and upright, and widely separated from the articular facet for the tubercle of the rib. On the centrum of this vertebra lower down is a second much larger rugose articular facet. On the eighth thoracic vertebra the upper articular process disappears altogether and is replaced by a transverse process on a lower level, with a facet at the free end for the rib. On the ninth thoracic the transverse processes are larger and nearly straight. They are longer on the first lumbar and incline a little forward. Those of the succeeding vertebræ are similar, but decrease gradually in length, while somewhat increasing in breadth. They are last traceable on the ninth caudal. On the eighth caudal they are perforated by a foramen.

All the vertebræ from the first cervical backward have neural spines as far as and including the eleventh caudal. The spine on the first thoracic is rather short, narrow and pointed. These spines increase in height in succeeding vertebræ as far as the sixth lumbar; at the same time the breadth increases antero-posteriorly and the tip becomes expanded. The spines are nearly equally high on all the succeeding lumbars, but begin to decrease on the caudals and disappear altogether on the eleventh caudal.

The anterior zygapophyses and metapophyses maintain a nearly constant position close to the top of the centra throughout the column, from the seventh thoracic backward, and are vertical, thin, and oblong, squared or rounded. They begin to decrease in size noticeably on the first caudal, and on the seventh caudal are mere swellings at the sides of the nearly horizontal plate from which the neural spine springs. They are traceable as far as the twelfth caudal.

A ridge appears on the side of the neural arch near its base on the fifth caudal and is stronger and very marked on those following, to the ninth caudal. A ridge unites the anterior and posterior facets for the chevrons on the ninth and succeeding caudals.

Barnegat City (female).—Unlike the Newport skeleton, there are no neural spines on the fifth, sixth, and seventh cervicals. The spine on the first thoracic vertebra is quite short and sharp, and on the second, third, and fourth thoracics also is rather pointed, though of increased length. There is no metapophysis on the seventh cervical.

On the seventh thoracic the facet for the tubercle of the rib, instead of being very prominent, becomes inconspicuous. The metapophysis is flat and squared, and there is no lower facet on the side of the centrum. On the eighth thoracic the metapophysis is thin, squared, and vertical, and a well-formed transverse process appears on the side of the centrum. The transverse processes of the ninth thoracic are a little curved backward, and on the first lumbar and succeeding vertebræ bent forward. These processes are less tapering on all the lumbars than in the Newport skeleton. They disappear on the eighth caudal. None is perforated.

The longest neural spine is on the sixth lumbar, and on all the lumbars both the anterior and posterior edges are somewhat convex. Hence their shape is rather different from those of the Newport skeleton, in which the anterior margins are somewhat concave. The tips of the spines are rather suddenly expanded. The spines of the caudals are rather more expanded at the tip and more inclined backward than in the Newport skeleton. They disappear on the eleventh caudal.

The horizontal plate joining the metapophyses is noticeable on the fifth caudal. The ridge on the side of the neural arch is first noticeable on the fourth caudal and is very strong on the fifth, sixth, and seventh. The metapophyses are last traceable on the twelfth caudal.

Charleston (female, jr.).—This skeleton resembles the Newport one as regards the facets for the articulation of the tubercles of the ribs, except that the seventh thoracic resembles the sixth and has no lower facet on the side of the centrum. The transverse processes of the ninth thoracic are rather strongly curved backward, while those on the last thoracic and first lumbar are nearly straight. On succeeding vertebræ they are inclined forward. They are last traceable on the eighth or ninth caudal (vertebra 35 or 36). None is perforated by a foramen.

Though the vertebræ are defective, there appear to have been no neural spines on the fourth to the seventh cervicals, inclusive. The spine on the first thoracic is short, and on the first to the fourth is pointed. The spine disappears on the tenth caudal (vertebra 37).

The metapophyses assume the vertical position on the eighth thoracic. The last of these processes is barely traceable on the tenth caudal (vertebra 37). The ridge on the side of the neural arch is well marked on the fifth to the ninth caudals, inclusive. On the seventh caudal (vertebra 34) the anterior and posterior facets for the chevrons are united on the right side, and on the eighth caudal and succeeding vertebræ on both sides.

CERVICAL VERTEBRÆ.

Barnegat City (female).—The first four cervicals are united. The foramen above the anterior articular facets of the atlas is complete, and the edges of these facets are raised. The inferior lateral process is flat, broad, and strongly bent backward.

Second cervical: Inferior lateral process nearly as long as that of the first cervical; broad, flat, and bent backward parallel with the process of the first cervical. Superior lateral process short, strong, and flat. A large incomplete foramen between it and the inferior process.

Third cervical: A short, conical inferior process, curved forward.

Fourth cervical: Similar, but with smaller and shorter inferior process. Neural arch and spine complete; the latter fused with the preceding spines. Arch not reducing the size of the neural canal.

Fifth cervical: Arch and spine broken. Arch nearly as broad as the anterior epiphysis of the centrum. Inferior lateral process short, straight, and directed obliquely outward.

Sixth cervical: Spine broken. Arch complete, nearly as wide as the anterior epiphysis. Inferior lateral process short, thick, knobbed, and directed obliquely outward and a very little forward. The left longer.

Seventh cervical: Spine obsolete. Arch complete, as wide as the anterior epiphysis. No superior lateral process or metapophysis. A thick articular facet for the head of the first rib on the middle of the side of the centrum. No inferior lateral process.

Fused spines of the first to fourth cervicals bent backward; the mass broad antero-posteriorly and rounded at the tip.

Newport (male).—First cervical with the foramen over the anterior articular facets incomplete, and the borders of the facets less raised. The facets also broader and more declined. Inferior lateral process thicker, somewhat tapering, and nearly transverse.

Second cervical: Inferior lateral process much shorter than that of first cervical, about parallel with it, but with the tip bent forward. Superior lateral process short, thick, and bent backward; joined to the inferior process on the right side, inclosing an oval foramen.

Third cervical: A short, straight, triangular superior process on the right side; that on the left short and blunt. Inferior lateral process long, thick, club-shaped, and curved backward.

Fourth cervical: Inferior lateral process similar to the last in shape, but shorter, broad and flat, and only slightly curved backward. Neural arch and spine separate from those of the third cervical; the arch rather smaller than those preceding it, and reducing the size of the neural canal.

Fused spines of the first to third cervicals nearly vertical, rather high, and obtusely pointed.

Fifth cervical: Spine pointed and quite long. Arch complete. Inferior lateral process short, squared, flattened, and directed outward obliquely.