SHOULDER-GIRDLE 



47 



From its I'ower end two bones (Fig. 12, Ct, Co; Fig. 11, 

 cor) pass directly inwards, parallel with one another, to end 

 in a plate of cartilage (^Co^), which meets with its fellow 

 of the opposite side in the middle line of the chest (?//). 

 The more anterior of these (C/) is a narrow bone and 

 is called the clavicle or collar bone, the posterior one is 



Fig. 12. — The shoulder-girdle of the Frog from the ventral aspect. 

 Co. coracoid ; Co . epicoracoid ; CI. clavicle ; Ep. epl-and omo-sternum ; G. glenoid 

 cavity ; Fe. fenestra between procoracoid and coracoid ; KC. cartilage separating 

 scapula and clavicle ; Kit. xiphisternum ; ;;/. junction of epicoracoids ; Ji". 

 scapula, St. sternum. (From Wiedersheim's 0/;//ii?-a//t'f .^/wa^i'wj'.) 



broader and is know'n as \)o.t coracoid {Co). Between the 

 scapula on the one hand and the clavicle and coracoid on 

 the other, there is a cartilaginous interval {KC), the posterior 

 edge of which is scooped out into a depression, the glenoid 

 cavity (Fig. 12, G ; Fig. 11, ^'■/), for the articulation of the 

 upper-arm bone. 



