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13. Long Branch.—Portions of several walrus skulls have been found on the beach at Long Branch. Two of these were described and figured by Leidy in 1867 (Trans. Amer. Philos. Soc., vol. XI, p. 83, plate IV, figs. 1, 2, plate V, fig. 1). One skull, lacking the lower jaw, some of the right hinder part of the cranium, and the exserted portion of one tusk, was discovered in 1853. The other specimen, discovered about 1856, furnished the front of the skull as far back as the middle of the palate. Both belonged to old individuals. Leidy concluded that the animals which had possessed these skulls belonged to the existing species Odobenus rosmarus. He surmised that they had been floated to the New Jersey coast on fields of ice or perhaps had lived there during the Glacial period. The skull which was found in 1853 is now in the collection of the Philadelphia Academy; the other is in the collection of the New Jersey Geological Survey. Recently, Mr. Samuel N. Rhoads has studied these skulls. He had also for examination the skull from Sable Island, which has been mentioned. He concluded that these skulls belonged to a species distinct from O. rosmarus and which might bear DeKay’s name, O. virginianus.

It does not appear to the present writer that Rhoads has successfully maintained his proposition. He did not have at hand a sufficient number of skulls of the existing Atlantic walrus to present all the variations that occur in that species. Of course, the number of fossil specimens was very limited. In discussing Rhoads’s conclusion, it will be of advantage to consider a part of a skull which belongs to the Marsh collection in Yale University. This specimen consists of the anterior half of the skull, without the tusks and without the other teeth. It was found at Kitty Hawk, at the mouth of Albemarle Sound, just north of latitude 36°. It is thoroughly fossilized; and, having been found so far south, it may be safely regarded as having belonged to the species which inhabited the New Jersey coast during the Pleistocene.

For purposes of comparison, such measurements are here given as can be obtained from the skull; likewise the corresponding measurements of a specimen from Sable Island, No. 199528 of the U. S. National Museum, and of another, No. 22014 of the National Museum, brought from Ungava Bay. Unfortunately, the basilar length of the fossil can not be determined, nor the width of the mastoids.

Measurements of skulls of walruses, in millimeters.
	Kitty Hawk.	Sable Island.	Ungava Bay.
From front of premaxillæ to rear of vomer	183	167	205
From front of tusk to optic foramen	188	177	195
From oral border of premaxilla to upper border of nasal opening	110	96	100
Greatest width across maxillæ	160	136	177
Least width at front of orbits	105	106	146
Least width at temporal fossæ	75	62	70
Width between the sockets for tusks	75	75	85
Length of row of teeth	82	60	83
Space between incisors	40	36	32
Space between last molars	62	60	53
Long diameter of tusk at base	34	26	38

The nasal bones of the fossil are so thoroughly consolidated with each other and with the adjoining bones that their dimensions can not be determined. There is no reason, however, for supposing that the length was greater than 70 mm.

The grinding teeth of the fossil do not show the larger size that we might expect from Rhoads’s determinations and from comparison with Leidy’s illustrations. The second socket was almost exactly the diameter of the same socket in the Sable Island specimen measured. The third socket is larger than that of the skull from Sable Island. The sockets for the first molars are very small and shallow; the socket for the left incisor is still smaller, while that for the right incisor is wholly effaced. The diameter of the socket for the second molar is much shorter than that of the corresponding socket in the Ungava Bay specimen. In the latter, the left incisor is present and large, but the other is missing and the socket is nearly filled up. It is evident that the teeth are extremely variable in both size and the number present.

Rhoads has found that the incisive foramina of the fossil skulls in his hands are placed high above the alveolar borders. In the North Carolina specimen this height is 32 mm.; in the Sable Island specimen in the U. S. National Museum, 30 mm.; in the Ungava Bay specimen, about 22 mm. Nor does the distance between the sockets for the incisors in the fossil from North Carolina agree with that dimension in the two specimens from Long Branch.

Despite the differences shown in the measurements in the table given above, the writer must conclude that there are not as yet sufficient reasons for regarding the Pleistocene walrus of the Atlantic coast as specifically different from the existing form.

Dr. Albert Reid Ledoux, mining engineer, of New York City, when a young man bathing at low tide at Long Branch, found a skull of a walrus. This was given to Professor John S. Newberry and is now probably at either Columbia University or the American Museum of Natural History. At the same time and at the same spot was a heel-bone of Megatherium, now in the American Museum (p. 31). It is very improbable that these two animals lived there at the same time.

According to recent publications of the Geological Survey of New Jersey (Salisbury, Report for 1897, p. 19, pl. I; Lewis and Kümmel, Bull. No. 14, p. 120, with Geologic Map of New Jersey, 1910–1912), Long Branch is situated on the Cape May formation. This is regarded by the geologists just quoted as corresponding in age, in great part at least, to the Wisconsin stage. When this deposit was laid down, the New Jersey coast was depressed from 35 to 50 feet below its present level. It seems very probable that at that time the walrus was living there and that the skulls found have been washed out of this deposit by the waves during storms. Nevertheless, the finding of Megatherium at Long Branch shows that there are deposits present which belong probably to early Pleistocene.

Dr. H. B. Kümmel, State Geologist of New Jersey, has informed the writer that a strip 0.25 to 0.75 mile back from the ocean in the region about Long Branch probably belongs to the Recent time. He states that one would be safe in concluding that the skulls of the walrus were found in deposits not older than the Cape May and that they may have occurred in more recent beds. Against the view that the walruses found along this coast lived there during the Recent period is their well-fossilized condition.

14. Ocean Grove, Monmouth County.—In 1910, after a storm, a part of a skull of a walrus was found on the beach at Ocean Grove, New Jersey. This is still in the possession of the finder, Mr. W. S. Hidden, who furnished the writer with photographs of the specimen. It consists of the front of the skull extending back to the bases of the zygomatic arches, and containing portions of both tusks and most of the teeth. There is no likelihood that this specimen belonged to any other species than Odobenus rosmarus, and it was probably washed out of the same deposits as those which furnished the specimen found at Long Branch.