170 ODOB^NUS OBESUS PACIFIC WALRUS. 



witliin tliirty degrees of the western limit of the range of the 

 Pacific animal. In view of these facts, the qnestion arises as 

 to whether the Atlantic species may not occasionally pass along 

 the northern coast of Asia so fiir as to sometimes reach the 

 habitat of the Pacific species. 



I^ToMENCLATURE. The first specific name applied to the Pa- 

 cific Walrus is ohestis, given by Illiger in 1815, in his " Ueber- 

 blick den Siingethiere nach ihrer Yertheilung fiber die Welt- 

 theile."* In this paper this name is three times used as a dis- 

 tinctive aijpellation for the Pacific Walrus, namely, (1) in his 

 list of the species of Northern Asia, in which " TricJiechus ros- 

 marus^^ and " TricJiechus ohesns^^ are both given; (2) in his list 

 of the species of North America ; and (3) in his remarks respect- 

 ing the first-named list. In these remarks (1. c, p. 75) he says^ 

 "Die beiden Arten des Walkosses, Trichechus obesus wnd [T.] 

 Bosmarus, sind schon bei Nord-Asien vorgekommen." For Eu- 

 rope he gives only T. rosmarus (1. c, p. 50), respecting the dis- 

 tribution of which he says, " Der TricJiechus Bosmarus, das Wall- 

 ross, lebt an den eisigen Kusten von Nord-Europa, Nord-Asien^ 

 und des ostlichen Nord-America " (1. c, p. 01). It is thus not 

 quite clear whether he considered his T. rosmarus to have a 

 complete circumpolar range, with T. ohesus as a second species^ 

 occurring only on the northeastern shores of Asia and the north- 

 western shoresof North America, or whether, as is more probable,, 

 he merely meantthat T. rosmarus ranged eastward along the Arc- 

 tic coast of the Old World to the northern shore of Western Asia 

 (as is the fact), and was replaced on the Pacific shores of Asia and 

 America by T. oTjcsus. In either case he recognized as a distinct 

 species, under the name T. oJjcsus, the Walrus of the North Pa- 

 cific and adjacent portions of the Arctic Ocean. In the same 

 paper is also a reference to a TricJiecJius " divergens,''^ respecting 

 which he thus observes : "Auser dem schon bei Euroi^a erwiihn- 

 ten Wallross, TricJiecJius Eosmarus, findet sich an der westhchen 

 Nord-Amerkanischen und nahen Ost-Asiatischen Kuste, und 

 dem Eise dieser Meere, vielleicht aber auch an der ganzen Kiiste 

 des Eismeers das von Cook beschriebene und abgebildete Wall- 

 ross, das ich wegen raehrerer Verschiedenheiten, besonders der 

 Hauzahne, als eigne Art unter dem Namen divcrgens aufge- 

 fuhrt habe " (1. c, p. 08). He thus, in the same paper, appears to 

 recognize two species of Pacific Walruses. The name divcrgenSy 



*Ablian(l. der Akad. der Wisseusch. zu Berlin, 1804-1811, (1815), pp. G4, 

 70, 75. 



