286 CLASSIFICATION OF VERTEBRATES. 



Salamandra, Pleurodeles, etc., the first two genera dating from 

 the European miocene. Megalotriton, eocene. 



FIG. 284. Siredon lava of Ainblystoma, from Hertwig, after Dumeril and Bibron. 



SUB-CLASS III. ANURA (SALIENTIA). 



Tailless in the adult condition, the caudal vertebrae being 

 reduced and fused to a urostyle ; vertebras usually procoelous ; 

 frontoparietals fused ; sphenethmoid present ; hind legs elongate 

 and fitted for leaping, the proximal row of tarsals greatly elon- 

 gate ; a marked metamorphosis, the tadpoles being vegetarians, 

 the adults carnivorous. The anura contains the frogs, toads, 

 tree-toads, etc., the group being best developed in North Amer- 

 ica and in the tropics. Its origin is uncertain, but probably was 

 from some stegocephalian ancestor. 



ORDER I. AGLOSSA. 



Tongue lacking ; the Eustachian tubes open together into 

 the pharynx ; epicoracoids free, but not overlapping. Xenopus 

 (DactyUtkrd)t from Africa; Pipa, the Surinam toad (p. 281), 

 from South America. 



ORDER II. ARCIFERA. 



Tongue well developed ; shoulder girdle arciferous (p. 278), 

 the coracoids of the two sides overlapping ; Eustachian tubes 

 widely separate. The BUFONID^: includes the toads, in which 

 the jaws are toothless, the toes webbed, but without suckers at 

 the tips ; parotid glands prominent. Bufo, the common toad. 

 The genus appears in the eocene. The PELOBATID/E differ in 

 having teeth. Pelobates first appears in the miocene. ScapJn- 



