PLATE 6 



EXPLANATION OF FIGURES 



20 Shield-like plate on ventral side of Pipa dorsigera. Adult female, upper 

 view. Would seem to indicate that sternum and coracoids were at one time 

 structurally one; omosternum but feebly separated from coracoidal portion. 

 After Parker. 



21 Bufo vulgaris. First summer. Lower view. After Parker. 



22 Large specimen of Siredon pisciformis. Sternum cut off from coracoids 

 in adult, but retain evidences of having come from the overlapping epicoracoids. 

 After Parker. 



23 Dactylethra capensis. Adult female. After Parker. 



24 Note the beginning of sternal bands in Calamites cyaneus. Compare 

 with same stage in low-type reptile. After Parker. 



CI, clavicle OSt, omosternum 



Cr, coracoid PCr, precoracoid 



Crf, coracoid fossa Sc, scapula 



ECr, epicoracoid SSc, suprascapula 



Gl, glenoid St, sternum 



102 



