THE BATRACHIA OF NORTH AMERICA. 



255 



Tlie families of this suborder differ as follows : 



L Kibs present (Discosi'lossoiclea Gill). 



Vertebrie opisthoccel ; sacral diapophyses dilated ; steruum bit'arcate. 



Discoglossidcu. 



II. Ribs absent (sternnni uot deeply bifurcate). (Bufonoidea Gill). 

 A. No teeth (vertebra^ proc(Bl). 



Diaxjopliyses of sacrum dilated Bufonidau 



Diapopbyses of sacrum not dilated Dendroj)]ir!jn.iscidw. 



AA. Maxillary teeth 0l]l3^ 



Vertebrte opisthoccel ; sacral diapophyses dilated ; urostjde distiuct. 



Asterophrydidw. 



Vertebrte procoel ; sacral diapophyses dilated ; urostyle distiuct; ungual 



phalanges conic Felodytidw. 



Vertebrai proccel ; sacral diapophyses dilated; ujostyle confluent with 



sacrum ; ungual phalanges conic ScapMopkUe. 



Vertebrae procosl ; sacral diapophyses dilated ; urostyle distinct; uugn;il 



phalanges a curved claw with globular base Hylida'. 



Vertebr;B procad; sacral diapophyses not dilated; tirostyle free ; ungual 



phalanges conic^ sometimes transverse at apex Cystignathidw. 



AAA. Maxillary and mandibular teeth j)reseut. 



Sacral diapophyses dilated , .^. Amphignathodontidw. 



Sacral diapophyses not dilated Hemiphractidw. 



Of the above families, four are fouud witbiu the boundaries of the 

 Nearctic Eealm. These are the Bufouidte, Scaphiopidte, Hylidoe, and 

 in a very few representatives, the Cystignathidaj. Three of the families 

 are confined to the E^eotropical Eealm — the Dendrophryniscidte, the 

 AmphignathodontidiB, and the Hemiphractidte. The Hylidte belong- 

 to this fauna and the Australian, with a large representation in the 

 IsTeartic and a very small one in the Pakearctic Jiealms. It is totally 

 wanting from the Ethiopian. The Discoglossidte is European, with one 

 genus in ISTew Zealand. It is the only family well represented by ter- 

 tiary forms. The small family of the Asterophrydidaj are Palteotropical 

 and Australian, and the few Pelodytida^, Pal neotropical and Palaearc- 

 tic. The large family of the Cystiguathidai are Neotropical and Aus- 

 tralian only. The Bufonidse are cosmopolitau, and the ScaphiopidiT3 

 Nearctic and Pahiearctic. But the greater number of the Arcifera are 

 i!^eotropical. 



We are at present acquainted with 501 species of this suborder, 

 which represent 84 generic types. They represent the families in the 

 following proportions and regions : 



Genera. 



Species. 



5 



8 



4 



6 



3 



4 



4 



7 



16 



]89 



1 



1 



3 



8 



35 



174 



14 



102 



Distributiou. 



Discoglossidfe 



Asterophrydidas 



Pelotly tidse 



SoaphiopidfB 



Hylidaj 



Amphignathodontidse 



Hemiphraotidas 



Cystignathidffi 



BufonidfB 



E. Pala?.arctica (Austndis). 



R. Paheotiopica, Australis. 



li. Pakeolropica, Pakiearctica. 



E. Palajarctica, Nearctica. 



(K. Palaiocropica) R. Palaearctica, Nearctica, Neo- 



tiopica, Australis. 

 E. Neotropica. 

 R. Neotropica. 

 R. Neotropica, Australis. 

 Cosmopolite. 



