556 AMPHIBIA. 



the obstetric toad — Alytes obstetruans, the male of which carries 

 the eggs on his bacl: and legs : Hylodes in tropical America, 

 with rapid development without metamorphosis : 



the South American Ceratophrys, of which some species have 

 bony plates in the skin of the back : Pelobates, which like 

 many others lives for the most part underground : the 

 brightly coloured tree-toads, such as Hyla, with adhesive 

 discs at the ends of the digits ; Nototrema, with a dorsal 

 egg-pouch in the females : Liopebna hochstetteri, the only 

 Amphibian in New Zealand, 

 (f) The tongueless Surinam Toad (Pipa amerkana), in which the 



eggs develop in pouches on the back of the female ; and the 



allied Ethiopian genus Xeiwpus, with a "tentacle" extending 



backwards on each side of the head. 



Order Urodela or Caudata. 



The tail persists in adult life ; the body is elongated ; the limljs are 

 weak when compared with those of Anura. 



(a) Forms like Proteus: — Two extant ^ai^xn Proteus 3.vid- Necturus 

 both with persistent gills. Several species of Proteus inhabit the 

 water in the caves of Carinthia and Dalmatia in Austria. The 

 gills persist, there are two pairs of limbs. The eyes are de- 

 generate, the colours are pale, as we should expect in cave- 

 animals. Two species of Necturus (or JMeuobranchus) occur 

 in North America, in rivers and lakes, such as those of the 

 Mississippi and Ohio basins. The pigment of the skin is well- 

 developed. 



(/') Forms like Siren: — Two extant genera, Sirett and Pseudobranchus, 

 both North American, both with persistent gills, with only the 

 anterior limbs. 



(c) Forms like the newts and salamanders ; —The North American 

 Aniphiuvia, with two pairs of rudimentar)' legs, with a slit per- 

 sisting in adult life as a remnant of the gilled state ; Alegalo- 

 batrachiis or Cryptobranchiis ina.ximus, the largest living Amphi- 

 bian, found in Japan and Thibet, attains a length of three 

 feet ; Amblystoma and its gilled form the Axolotl ; Desmognathus 

 fusca, the common water salamander of the United States, lays 

 its eggs in a wreath which one of the sexes twines round its 

 body ; Salaniandra viaculosa and S. atra^ both European, both 

 viviparous; the newts — Triton or Molge — of which Triton 

 a/pestris becomes sexually mature while still larval. 



Order GYMNOritiONA or Apod.a. 



Worm-like or snake-like forms, subterranean in habit ; without limbs 

 or girdles or tail ; with dermic scales concealed in the skin ; in at least 

 some forms, gills occur in early life ; the eyes are rudimentary; peculiar 

 " tentacles " are connected with the orbit, and are perhaps equivalent 

 to the "balancers," which occur in larval Urodela in front of the first 

 gill cleft. Ciccilia in West Africa, Malabar, South America; Siplwnops 



