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]