XI.] UNGULATA. 173 



closed in the living animal by membrane. Most of the 

 Deer and Antelopes have also a large depression on the 

 facial surface of the lachrymal bone, called the suborbital or 

 lachrymal fossa, though it has nothing to do with the tears, 

 but lodges a glandular fold of the integument, which secretes 

 a peculiar unctuous and odorous substance. In most Deer 

 the orifice of the lachrymal canal is double, and situated on 

 the margin of the orbit, whereas in most of the hollow- 

 horned ruminants it is single and placed well within the 

 margin. There are however exceptions in both cases. 



In the Deer the axis of the face is nearly in the same 

 line with that of the cranium, so that when the basicranial 

 axis is horizontal the nose is directed forwards instead of 

 downwards, as in the Sheep and Ox. The animals of this 

 family have no permanent horn cores continuous with the 

 cranium and ensheathed by true horns, but have short pro- 

 cesses on the frontal bones {pedicles)^ from which branching 

 antlers of true osseous structure are annually developed 

 and shed. These, as a rule, are only present in the males, 

 while the horns of the Bovidce and AntilopidcE are usually 

 common to both sexes. 



Among the Antelopes, the Saiga {Saiga tartarica) is very 

 remarkable for the conformation of the upper part of the 

 face. The anterior nares extend backwards almost to a 

 level with the front edge of the orbits, and have an unusual 

 vertical expansion. The nasal bones are aborted or coa- 

 lesced with the frontals. The turbinals are very short. 

 The lachrymals enter largely into the side walls of the 

 anterior nares. The ascending processes of the premaxillae 

 are small, and very widely separated from the nasals. In 

 the living animal the edges of these greatly expanded nariai 

 apertures are continued forwards into a truncated, almost 

 proboscidiform muzzle without any bony support, giving the 



