DIFFERENTIAL CHAKACTERS. 



169 



sible seems evident from the fact of the existence, dnring por- 

 tions of the year at least, of areas of open water along those 

 portions of the Arctic coast snpposed to separate the habitats 

 of the two species. Fnrther than this, 1 have seen a sknll (now 

 in the Mnsenm of the Boston Society of Natnral History) which 

 Capt. Charles Bryant (certainly a trnstworthy authority) 

 assures me was taken by his assistant, on Walrus Island, in 

 the summer of 1871 or 1872, that agrees in every particular 

 with the skulls of the Atlan- 

 tic species. This skull hav- 

 ing been somewhat fantas- 

 tically painted (the lower 

 surface deep red and the 

 upper yellowish-white), led 

 me at first to doubt the cor- 

 rectness of the alleged local- Fig. 34. Odohwnus rosnarus. Young. 

 ity, supposing that if really obtained at the Prybilov Islands 

 it might have been brought there from some distant point. 

 This quaint ornamentation proves, however, an aid in fixing 

 the locality of its capture as Walrus Island. It differing so 

 widely from the form usually occurring in those waters, it at 

 once attracted attention, and was mounted on a bracket and 

 preserved as a curiosity, the i)aint being applied, as Captain 

 Bryant informs me, to facilitate its being kept free of dust ! 

 Captain Bryant states (in a letter to the writer) that he has 

 himself "seen two specimens like it," but adds that he "did not 

 succeed in killing them." Hence, of course, their resemblance 

 to the one now in question is 

 only presumed, the animals 

 being only seen alive. He 

 writes, further, that this 

 "head" was recognized as 

 "different from any before 

 seen there." I will merely add 

 that this skull is indistin- Fig. 35.Odol)cenus ohesus. Young. 

 guishable in any essential detail from skulls of corresponding- 

 age from the Atlantic waters, and points to the occasional oc- 

 currence of Odohcenus rosmarus within the habitat of Odobwmis 

 obesus. As von Middendorff has shown (see antea, p. 78), the 

 Wabus (presumably the Atlantic species) has occurred much 

 further to the eastward than the limits assigned it by von Baer, 

 he having traced it, satisfactorilj- to himself, apparently, to 



