KUMINANTIA 369 



sides, so as to look like a single hoof cloven ; whence the name 

 " cloven-footed," also given to these animals. The perfect cir- 

 cumscription and definition of this order, so desirable by the 

 systematic zoologist, is indeed invaded, in the actual Rumi- 

 nantia, by certain peculiarities of the camel tribe. 



In entering upon the evidences of the first appearance in 

 this planet of the order of animals, which now are the most 

 valuable to man, it may be well to call to mind the characters 

 of the Anoplotlwrium. The upper true molars have two 

 double crescents, convex inwards, one of the inner ones being 

 encroached on by a large tubercle, the reduced homologue of 

 which may be seen in the internal inner space of the crescents 

 in the ox and some other Euminants. The lower true molars 

 also, at one stage of attrition, form crescentic islands of enamel, 

 with the convexity turned outwards, as in Euminants, the last 

 molar having the accessory crescent behind. The functional 

 hoofs were two in number on each foot, but must have resem- 

 bled those of the camel tribe in shape ; the scaphoid and 

 cuboid of the tarsus were distinct also, as in the Camelidcc; 

 and the metacarpal and metatarsal bones were divided, as in 

 the water musk-deer (Moschus aquaticus), and in the embryos 

 of all Euminants. The dentition of the extinct Dichodon (figs. 

 102, 103) made a still nearer approach to that of the Eumi- 

 nants. The chief distinction of this and other extinct Herbi- 

 vores with double crescentic molars is the completion of the 

 upper series of teeth by well-developed incisors. But the pre- 

 maxillaries in the new-born camel contain each three incisors, 

 one of which becomes fully developed. The Camelidce are horn- 

 less, like the Anoplotherioids and Dichodonts ; and with one 

 exception — the giraffe — all Euminants are born without horns. 



Thus the Anoplothcrium, in several important characters, 

 resembled the embryo Ruminant, but retained throughout lite 

 those marks of adhesion to a more generalized mammalian 

 type. The move modified or specialized form of hoofed animal, 



2 r. 



