5 86 



AMPHIBIA. 



or humerus, a fore-arm in which the inner radius and the 

 outer ulna are fused, a wrist or carpus including two 



FIG. 316. Pectoral girdle of Rana esculenta. 

 After Ecker. 



The cartilaginous parts arc dotted. -/>., Episternum ; om., omo- 

 sternum ; Ep.c.^ epicoracoids ; st. t sternum ; jr., xiphisternum ; 

 cl., clavicle with underlying precoracoid cartilage ; cp., cora- 

 coid ; Sc., scapula; S.sc., supra-scapula ; GL, glenoid cavity 

 for humerus. 



proximal and three distal elements, and a central piece 

 wedged in between them, five metacarpal bones, of which 

 the first corresponding to the absent thumb is very 



FIG. 317. Side" view of frog's pelvis. After Ecker. 

 //., Ilium; /*., ischium ; P6., pubis; Ac. t acetabulum. 



small, and four fingers, of which the two innermost have 

 two joints or phalanges, while the two others have three. 



The pelvic girdle is shaped like a V, or like a pair of 

 tongs. The ends are cartilaginous and articulate with the 



