80 



OSTEOLOGY 



than before backward. It is bounded behind by the 

 first thoracic vertebra; in front, by the upper border 

 of the sternum, and on either side by the first rib. 



FIG. 40 



First thoracic 



The thorax. Ventral view. (Gray.) 



It slopes downward and forward so that the anterfor 

 boundary is on a lower level than the posterior. The 

 anteroposterior diameter is about 2 inches (5 cm.), 



