198 PROCEEDINGS OF THE ACADEMY OF [1898. 



research in the Academy of Natural Sciences that the facts con- 

 tained in this paper are now made accessible. Mr. Woolman's at- 

 tempt to locate DeKay's type of T. virginianus resulted in the dis- 

 covery that this specimen was destroyed by fire with the other ob- 

 jects of natural history in the museum of the old New York Lyceum 

 of Natural History, now known as the New York Academy of Sci- 

 ences. 



The loss of this specimen, together with the inadequate descrip- 

 tion of its characters and the crude nature of DeKay's figure of it 

 make the use of the name virginianus for an extinct species of wal- 

 rus questionable, even in the event of proof that the other fossil speci- 

 mens represent a different species from that now existing. However 

 if the characters of these latter can be shown to indicate such a state 

 of affairs and at the same time show no radical differences from what 

 we know of the type of virginianus, it is eminently proper that that 

 name should be applied to them, and the extinct walrus of the 

 glacial period be so distinguished from Rosmarus rosmarus. 



As Leidy has already shown, DeKay's brief diagnosis of virgin- 

 ianus 5 is equally applicable to Rosmarus rosmarus, and had he not 

 figured the specimen, we would now, on account of the loss of the 

 type, be forced to make virginianas a probable synonym of rosmarus. 

 The fact, however, that the type was a fossil and was figured, and 

 that it, in all probability, represented the same species as the fossil 

 skulls from New Jersey and Sable Island, makes the name as tena- 

 ble as ever for a possible species of fossil walrus. 



The characters of all the fossil specimens show conclusively their 

 closer affinity to rosmarus than to obesus of the Pacific Ocean, ex- 

 cept in the relative size of the molars. In this respect they ap- 

 proach more nearly the Pacific species as represented in the skull 

 of an old male from Alaska, in which the molars are very large and 

 rounded. The canine tusks of the fossil specimens are characteris- 

 tic of the rather short, heavy, decurved and spreading form seen in 

 rosmarus. In respect of the ratio of the extreme facial width across 

 the maxillaries to the greatest occipital width, it is noticeable that 

 the fossil specimens come much nearer to obesus, in which the differ- 

 ences between these dimensions are much less than in rosmarus. In 

 the fossil specimen from Nova Scotia the maxillary expansion is 

 203 mm., and the paroccipital expansion (adding 10 mm. for wear) 



5 It reads: "Cheek teeth with obliquely truncate crowns, not ridged; the 

 second smaller than the first." 



