286 CLASSIFICATION OF VERTEBRATES. 



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

 the European miocene. Megalotriton, eocene. 



FIG. 284. Siredon lava of Atnblystoma^ 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 ; vertebrae 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 

 {Dactylethrd), 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. Scapin- 



