6o 



ELEMENTS OF MAMMALIAN ANATOMY 



nine in some of the Edentata. The human sacrum is composed 

 of from four to six vertebra'. The same is true of the gorilla, 



Fig. 29. — Ventr.^l Aspect of the Bones of the Thorax. The numbers 

 on the vertebral or bony portions of the ribs indicate the names of the ribs. The 

 numbers of the last four ribs are placed just craniad of them, 



c. Cartilaginous part of the first rib; cr, cartilaginous disc between the bodies 

 of the vertebrae; en, xiphoid process; hd, heads or capitula of ribs; m, manubrium; 

 mr, attachment of twelfth to the eleventh rib; n, free termination of thirteenth 

 rib; r, attachment of the eleventh to the tenth rib; /6, tubercle of first rib; /n, 

 transverse process of first thoracic vertebra; v, body of vertebra. 



chimpanzee, and orang. The caudal vertebra? vary greatly 

 in number in the different forms. In the adult human there 

 are present only four or five vertebra?, which form a single 



