EVEN-TOED UNGULATES (aRTIODACTYLA) 211 



its lining is a network of folds ; the adjoining com- 

 partment is lined with longitudinal folds like the 

 leaves of a book and is therefore called the " psal- 

 terium " or manyplies. These folds are of varying 

 depths ; some genera are characterised by two 

 depths of folds, some by three depths, and others 

 by four. 



There are three families of Pecora which may be 

 distinguished, in addition to other characters, chiefly 

 by the structure of their horns : (a) deer; (h) gii'aife ; 

 (c) oxen. 



Fam. Gervidse or Deer. 



The possession of antlers separates the deer family 

 from all other ruminants, the structure and growth 

 of which have been dealt with above. The antlers 

 are variously developed and branched in the different 

 groups of the family, and the parts of the antler 

 have their technical names. The main shaft is 

 called ^Hhe beam," the base of which is called 

 ^' the pedicel ^^ ; the first branch above the pedicel 

 usually directed forward is called ^' the brow tine^'; 

 the second branch from the beam is ^' the bay, or bez 

 tine"; and the third " the tray, or trez tine.'^ These 

 tines may bear secondary branches or points, the mass 

 of points at the summit of the antlers being called 

 " surroyals." In the elk and the fallow deer the 

 beam expands above into a " palm." At the base 

 of the antler there is a rough ring known as the 

 '' burr." It is just below the '' burr " that the beam 

 becomes weakened by a process of absorption when 

 the antler is about to be shed. Deer usually shed 



