46 INTRODUCTION. 



shaped fontanelle ; metacarpal and phalanges 

 of fourth finsfer not more massive than the 

 others ....... A. obstetricans. 



Fronto-parietal bones meeting iu the middle, 

 separating a large kite shaped f ontanelle in 

 front from a very small one behind ; meta- 

 carpal and phalanges of fourth finger very 



massive A. cisternasii. 



b. Vertebrae proccelous, without autogenous 

 ribs. 

 1 . Vertebrae with imbricate arches completely 

 covering the spinal cord above ; diapo- 

 physes of sacral vertebra very strongly 

 dilated, and sliding in a groove of the ilia ; 

 praecoracoid not entering glenoid cavity ; 

 omosternum cartilaginous ; sternum with 

 a bony style; long bones with cartilagi- 

 nous, non-calcified epiphyses ; three carpal 

 bones in contact with radius-ulna 



(Pelobatidje), 



a. A fronto-parietal fontanelle ; fronto- 



parietals distinct ; palatines absent ; 

 postero-median neural process of ver- 

 tebrae very short or absent ; sacral ver- 

 tebra with two condyles for nrostyle ; 

 astragalus fused with calcaneum; seven 

 bones in carpus ; four cartilaginous 

 elements in distal tarsal row Pelodytes. 



b. No fronto-parietal fontanelle; fronto- 



parietal single, rugose ; squamosal ex- 

 panded, plate-like ; dorsal vertebrae with 

 a long postero-median neural process ; 

 sacrum usually fused with urostyle ; 

 astragalus and calcaneum distinct ; eight 

 bones in carpus, three in distal tarsal 

 row Velobates. 



Squamosal not joining fronto-parietal ; ethmoid 

 reaching praemaxillaries . . P. fuscus. 



Squamosal forming with fronto-parietal a broad 



