432 PELOBATID^. 



9. PELOBATID^l. 



Discoglossidse, part., Asterophrydidae, Alytidse, part., Bombinatoridse, 



part., Giinth. Cat. Batr. Sal. 

 Asteroplirydidse and Scaphiopodidse, part., Cope, Nat. Hist. Rev. 



1865. 

 Asterophrvdidse, Pelodytidse, Scaphiopodidse, Cope, Journ. Ac. Philad. 



(2) vi. 1866. 

 Bombinatoridse, part., Alytidse, part., Discoglossidse, part., Mivart, 



Proc. Zool. Soc. 1869. 

 Pelobatidas and Asterophrydidae, Lataste, Actes Soc. Linn. Bord. 



xxx. p. 339. 



Upper jaw toothed; diapophyses of sacral vertebra strongly 

 dilated ; no ribs ; terminal phalanges simple. 



The coracoids and precoracoids are more or less strongly curved. 

 The omosternum is constantly present, but small and cartilaginous. 

 The sternum is a cartilaginous plate, or a bony style with cartilagi- 

 nous disk. 



The vertebrae are procoelian in most of the genera ; in Megalo- 

 johrys, and perhaps also in Asteroplirys, they are opisthoccelian, as 

 in the Diseoglossidce and Aglossa. But, in this case, this character 

 does not seem to be of such importance as was believed by some 

 authors. It has been noticed that, in some individuals of various 

 species, the intervertebral spheres do not become firmly attached to 

 either centrum at maturity * ; and one adult specimen of Xenophrys 

 rnonticola in the British Museum exhibits a very anomalous mode 

 of articulation, the fourth vertebra being biconcave, the fifth bi- 

 convex, the others procoelian. 



A fronto-parietal fontanelle is present in Pelodytes, absent in the 

 other genera. 



The pupil is vertically elliptic. 



Synojisis of the Genera. 



I. Coccyx and sacrum confluent ; toes extensively webbed. 



Sternum a cartilaginous plate ; tympanum present. 



1. Scaphiopus, p. 433. 

 Sternum with a bony style ; tympanum absent. 



2. Pelohates, p. 437. 



II. Sacral vertebra with two condyles for articulation with 



coccyx ; toes nearly free or very shortly webbed. 



Sternum with a bony style ; vomerine teeth on a level with the front 

 edge of the choanae ; diapophyses of sacial vertebra extremely 

 dilated 3. Peloiytes, p. 438. 



Sternum without bony style ; vomerine teeth in a long transverse 

 scries behind the choanse 4. Batrachopsis, p. 439. 



* Cf. Duges, ' Eecherches sur l'Osteologie et la Myologie des Batraciens,' and 

 Cope, Joura. Ac. Philad. (2) vi. I860, p. 67. 



