434 ORDERS OF MAMMALIA. 



Artiodactyle Ungulates. In fact, as the feet appear to be un- 

 doubtedly three-toed, it can only with some violence be consi- 

 dered here as belonging to the Artiodactyles. At the same 

 time, it shows many remarkable points of affinity to the Catne- 

 lidcE, and it may be regarded as a generalised type, presenting 

 resemblances on the one hand to PaltzotJierium, and on the 

 other hand to the Llamas (Auchenia). Only a single species is 

 known, which equals the Rhinoceros in size, and occurs in 

 Post-Tertiary or late Tertiary strata in South America. 



b. Moschidce. The second group is that of the Musk-deer, 

 characterised by the total absence of horns in both sexes, and 

 by the presence of canines in both jaws, those in the upper jaw 

 being in the form of tusks in the males, but being much smaller 

 in the females. 



The family Moschida is a small one, and is of little geologi- 

 cal importance. A species of Moschus, allied to the living 

 Musk-deer, has been found in India, and another form has been 

 indicated as occurring in the later Tertiary deposits of Europe. 

 The genus Amphitragulus has been founded upon remains from 

 the Lower Miocene of France ; and the nearly-allied Dremo- 

 therium has been discovered in the Miocene deposits of France 

 and Attica. 



c. Cervida. This family is of much greater importance than 

 that of the Moschida, including as it does all the true Deer. 

 They are distinguished from the other Ruminants chiefly by 

 the nature of the horns. With the single exception of the 

 Reindeer, these appendages are confined to the males amongst 

 the Cervida, and do not occur in the females. They do not 

 consist, as in the succeeding group, of a hollow sheath of horn 

 surrounding a central bony core, nor are they permanently re- 

 tained by the animal. On the other hand, the horns, or, as 

 they are more properly called, the antlers, of the Cerridce are 

 deciduous, and are solid. They are bony throughout, and are 

 usually more or less branched, and they are annually shed and 

 annually reproduced at the breeding season. They increase 

 in size and in the number of branches every time they are 

 reproduced, until in the old males they may attain an enor- 

 mous size. 



The living Cervida are very generally distributed, but no 

 member of the group has hitherto been discovered in either 

 Australia or South Africa, their place in the latter continent 

 seeming to be taken by the nearly-allied Antelopes (distin- 

 guished by their hollow horns). 



The true Cervida do not seem to make their appearance 

 before the Miocene period, in which they are represented by 



