40 ODOB^NUS ROSMARUS ATLANTIC WALRUS. 



to be only differences of a sexual character.* Stannius,t ten 

 yeajs later, cited the views of Temminck and Wiegmann (as 

 above given) respecting sexual differences in Walruses, but adds 

 nothing new to the subject. Lamont (see antea, p. 35) states 

 that the " tusks vary very much in size and shape according to 

 the age and sex of the animal." "Cows' tusks," he says, "will 

 average fully as long as bulls 7 , from being less liable to be broken, 

 but they are seldom more than twenty inches long and three 

 pounds each in weight. They are generally set much closer 

 together than the bulFs tusks, sometime overlapping at the 

 points, as in the case with the stuffed specimen at the British 

 Museum." He gives the length of tusks in the male as 24 inches, 

 and the weight as 4 pounds each. 



A skeleton, marked as that of a female, in the Museum of 

 Comparative Zoology, collected in the Greenland seas by Dr. 

 Kane, has the bones very light, soft, and porous, as compared 

 with those of male specimens. The skull (see figg. 1-3) is much 

 smaller, with the crests and ridges very slightly developed, and 

 the tusks long and slender, and overlapping at the points. This 

 skull, though of a rather aged individual, is 2 to 2| inches 

 shorter than male skulls of corresponding age, and about 2 

 inches narrower; but these figures scarcely express the real 

 difference between them, owing to the very much weaker devel- 

 opment and slighter structure of all parts of the skull, which 

 certainly has not one-half the weight of average adult male 

 skulls. The weaker structure is especially marked in the lower 

 jaw. The tusks, on the other hand, are several inches longer 

 than in any male skulls of the Atlantic species I have yet exam- 

 ined, but they are so much weaker and slenderer that their 

 weight is more than one-half less. The same difference of light- 

 ness and smaller size extends throughout all the bones of the 

 skeleton, indicating that the size of the animal in life was far 

 less than that of ordinary males. The very great length of the 



* Says Wieginann : " Hr. Fremery flilirt an, dass Hr. Temminck einen (nach 

 DeutlicTikeit der Nahte) iioch jungen Schadel des Reiclisimiseiuns niit aus- 

 gezeiciinet laugen diinnen Stosszahnen fiir den eines Weibchens gehalten 

 habe. Ic h erinnere mich aucli von Gronlandsfahren gehort zu haben, dass sich 

 das Weibchen dnrck liingero, dimnere, das Miinnchen clurch kiirzere, aber viel 

 dickere Stossziilme auszeiclme. Die geringere Entwicklimg der Hinter- 

 hauptleiste, die geringere Sell were der Knochen, selbst das Zuriickbleiben des 

 hintersten Backenzahnes im Oberkiefer konnte, wenn es wirklich nnr sexu- 

 elle VerscMedenheit sein sollte, mit Aualogien belegt werden." Arch, fur 

 Naturgesch., 1832, pp. 128, 129. 



t Mailer's Arch. fiir. Anat., 1844, p. 392. 



