16 



Sub-ordkr . — Firmisternia. 

 Family IV. — Ranidae. 



GENERA AND SPECIES. 

 Family I. — Bufo lentiginosis americanus. 

 Family II. — Scaphiopus holbrooki. 

 Family III. — Acris gryllus crepitans. 



Hyla andersoni. 



Hyla pickeringi. 



Hyla versicolor. 

 Family IV, — Rana virescens virescens. 



Rana palustris. 



Rana clamata. 



Rana sylvatica. 



Rana catesbiana. 

 Some of the family differences are as interesting as the 

 specific. These and differences in habitat are shown in the 

 following table: 



Bufonidae. 



No teeth. 



Sacral diapophyses dilated. 

 Urostyle with two condyles. 



Habitat everywhere except Australia. Headquarters, 

 South America. 



Scaphiopidae, 



Vomerine teeth ; a few undeveloped teeth in margin of 



jaw. 

 Urostyle confluent with sacrum. (No condyles). 

 Habitat, Northern Hemisphere. 



Hylidas. 



Maxillary and vomerine teeth. 

 Sacral diapophyses dilated. 

 Urostyle distinct. 

 Habitat, Europe and America. 



In Australia there are Hylas, but no toads or frogs. None 

 in the ^Ethiopian region. 



