520 



MANUAL OF ZOOLOGY. 



The dental formula, then, for a typical Ruminant animal 

 is 



The departures from this typical formula occur in the Camelidce 

 and in some of the Deer. Most of the Deer conform in their 



Fig, 200. Skull of a hornless Sheep (after Owen), i Incisors ; c Canines ; 

 in Molars and praemolars. 



dentition to the above formula, but a few forms (e.g., the Musk- 

 deer) have canine teeth in the upper jaw. These upper 

 canines, however, are mostly confined to the males ; and if 

 they occur in the females, they are of a small size. The denti- 

 tion of the Camelidce (Camels and Llamas) is still more aber- 

 rant; there being two upper incisors and upper canines as 

 well. The lower canines also are more pointed and stand 

 more erect than the lower incisors, so that they are easily 

 recognisable. The group of the Ruminantia includes the 

 families of the Camelidce (Camels and Llamas), the Moschidce 

 (Musk-deer), the Cervidce (Deer), the Camelopardalidce (Giraffe), 

 and the Cavicorhia (Oxen, Sheep, Goats, Antelopes). 



a. Camelidce. The Camels and Llamas constitute in many 

 respects an aberrant group of the Ruminantia, especially in 

 their dentition, the peculiarities of which have been spoken of 

 above, and need not be repeated here. In their feet, too, the 

 Camelidce are peculiar. The feet are long and terminate in 



