372 



METAZOAN PHYLA 



moist earth and coils her body about them. When hatched the larvae 

 are nearly mature. An alpine newt which occurs in mountain lakes in 

 Europe brings forth its young alive, the tadpole stage being undergone 

 and metamorphosis taking place in the uterus of the mother. 



396. Salientia. — The tailless Amphibia are, generally speaking, 

 divided into two types, those without a tongue and those with one. 

 Among those without a tongue is the curious Surinam toad. This is an 

 aquatic toad with very large hind feet and a short, broad head. During 

 pairing the o\aduct is protruded through the cloaca and passed forward 

 between the back of the female and the abdomen of the male. As the 



Fig. 261. — A common toad, Bufo woodhousii (Girard), of the family of true toads, 

 Bufonidae. Toads use temporary pools in early spring in which to deposit their eggs. 

 The young tadpoles are very small when hatched and remain in the tadpole stage only a 

 few weeks, at the end of which they metamorphose into small toads. These may require 

 4 to 5 years to grow to mature size. Warts on man cannot be contracted by handling toads. 

 (Photographed and contributed by George E. Hudsoyi.) 



eggs are passed from the oviduct, they are fertilized and spread over 

 the back of the female, to the surface of which they become firmly 

 adherent. Gradually they sink into pockets in the skin, each pocket 

 having a sort of lid. In these pockets the young develop until they 

 are prepared for independent life. The male of the European obstetrical 

 frog carries strings of eggs on his hind legs and releases the tadpoles in 

 water when they are ready to hatch. 



The tongued forms include both frogs and toads. There is no sharp 

 distinction between the two but usually a soft-skinned, partly aquatic 

 type is known as a frog (Fig. 268G), and a harder-skinned, more terrestrial 

 one as a toad (Fig. 261) . The true toads also have no teeth on either jaw. 



