642 



CHORD AT A. 



reticulum (re), thence to the many plies or omasum (o), and lastly to the 

 abomasum, or true stomach (a). Usually not only the canines but the in- 

 cisors of the upper jaw are degenerate, while the incisors of the lower jaw 

 are strong and the canines have taken the form and position of incisors. 

 The molars are seleriodont (have crescent-shaped cusps). With few excep- 

 tions they are of large size and many bear horns on the frontal bones. These 

 are larger in the males and may occur exclusively in that sex. In the sim- 

 plest case (giraffes) these are cones of horn free from the frontals and cov- 

 ered with skin. In others (Cavicornia) the horn cores fuse secondarily with 



FIG. 665. Stomach of sheep. (After Cams and Otto.) a, abomasum (true stomach); 

 o, omasum (manyplies) ; re, reticulum (honeycomb) ; rw, rumen (paunch). 



the frontals and are covered with a firm sheath of horn. Lastly, the horns 

 are outgrowths of the frontal bone, in which usually the outer coats are 

 lost and only the bone projects freely (antlers). These are shed yearly, 

 the new antler which takes its place being larger and consisting of a larger 

 number of branches or tines, thus constituting an index of age (Cervicornia). 

 CAMELOPARDALID^E (Devexa), giraffes, long-legged forms (two genera) from 

 Africa with persistent horns; teeth -$$ff, Giraffa. CERVID^E, deer, with 

 deciduous horns in the male. Cervus,* common deer; Alces,* moose; 

 Rangifer* reindeer; MOSCHID^E, horns lacking, males with enlarged upper 

 canines and with a musk gland (the source of the familiar perfume) on the 

 ventral surface; Moschus, central Asia. The TRAGULHWE, primitive Asiatic 

 and African forms, includes the chevrotain, Tragulus javanicus, the small- 

 est living ungulate. The CAVICORNIA include a large number of forms, 

 some of great economic importance; teeth fff. BOVID^E: Bos taurus, 

 domestic cattle, probably descended from three distinct stocks (B. primi- 

 genius, the aurochs, B. longifrons and B. frontosus); Bison,* including 

 B. europeus, the bison proper, and B. americanus* our * buffalo,' so near 

 extinction; Bubalus, the true buffalo of the Old World. OVHXE: Ovisaries, 

 sheep; 0. montana* big horn; Capra hircus, goat; Ovibos moschatus,* 

 musk ox. ANTILOPID^E: including a host of Old World forms (Antilope, 

 Oazella, Rupicapra tragus, the chamois, etc.) and Antilocapra americana,* 



