225 



NOTES AND QUERIES. 



MAMMALIA. 



The Use of the Giraffe's Bilobed Canine. — In the course of his 

 memoir on the Okapi, published last year in the ' Transactions ' of the 

 Zoological Society, Prof. Ray Lankester drew attention to the circum- 

 stance that all the living, and many (if not all) of the extinct members 

 of the Girajfida, are distinguished from other ruminants by the crown 

 of the outermost of the four pairs of lower front teeth (corresponding 

 to the canines of other mammals) are bifid, or bilobed ; this bilobed 

 structure having been observed in the Giraffe and the Okapi, as well 

 as in the extinct Sivatherium of India and the Samotherium of Southern 

 Europe. No explanation was at the time given for this departure from 

 the normal structure. 



Recently I have had an opportunity of watching carefully the mode 

 in which a Giraffe plucks the leaves from a bough. The leaves are 

 first grasped by the long and extensile tongue, and are then stripped 

 from the bough by being drawn between the lower teeth and the front 

 of the palate in such a manner that the twigs of the bough itself are 

 left practically uninjured. The lower front teeth act, in fact, as a 

 kind of comb in stripping off the leaves ; and I think there can be 

 little doubt that the broad bilobed crowns of the outer pair of teeth 

 have been developed in order to increase the breadth of this " comb," 

 and at the same time to render its comb-like action as efficient as 

 possible. 



Deer and cattle, when browsing, eat the twigs as well as leaves, 

 and since this difference in habit is correlated with a simple lower 

 canine, while there is almost certainly some good reason for the bifid 

 crown of that tooth in the Giraffe and its allies, there appears to be a 

 strong probability of the truth of the foregoing suggestion. Should 

 it be well founded it will be evident that the Sivatherium and other 

 extinct relatives of the Giraffe and the Okapi fed in the same manner 

 as those animals. — R. Lydekker. 



