40 ODOB^NUS EOSMARUS ATLANTIC WALEUS. 



to be only clLfferences of a sexual character.* Stamims,t ten 

 years later, cited the views of Teinminck and Wiegmann (as 

 above given) respecting sexual diiferences 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', 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 bull's tusks, . sometime overlai)ping 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 i^ounds each. 



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

 Oomparative 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 develoi^ed, 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 S(;arcely express the real 

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

 opment and slighter structure of all parts of the slcull, 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 Wiegmann : " Hr. Fremery fiilirt an, dass Hr. Temminck einen (nach 

 Dentlichkeit der Niilite) uocli jungen Scliiidel des EeicJismnseums mit aus- 

 gezeiciinet laugen dlinnen Stosszalmen fiir den eines Weibchens gelialten 

 habe. Icli erinnere micli aucb. von Gronlandsfabron gebort zu baben, dass sicb 

 das Weibcben diu'cb liiugere, diinnere, das Miinnclien durcb. kiirzere, aber viel 

 dickere Stosszlibno auszeicbne. Die geringere Entwickluug der Hinter- 

 hauptleiste, die geringere Scbwere der Knocben, selbst das Zuriickbleiben des 

 hintersten Backenzabiies im Oberkiefer konnte, wenn es wixklicb nur sexu- 

 elle Verscbiedenbeit sein sollte, mit Analogien belegt "werdeu." Arch, fur 

 Nahmjescli., 1832, pp. 123, 129. 



tMuIler's Arcb. fiir. Anat., 1844, p. 392. 



