THE ALLIES OF THE FROG: AMPHIBIA 343 



secretion from the oviduct. As a general rule one egg is laid at 

 a time ; occasionally two are inclosed in the same mass. The 

 young hatch in from twenty to thirty-five days, depending 

 on the temperature. In August they resemble Fig. 170, B. 

 Late in the fall they leave the water and live on land in 

 damp places beneath logs and leaves in the woods. They 

 are then of a beautiful red color and have a cylindrical tail 

 (Fig. 170, C). Several years are required to produce the 

 aquatic adult form (Fig. 170, E). 



Toads and Frogs. The members of the order Anu'ra (Gr. an, 

 without; oura, tail) undergo a well-marked metamorphosis. 

 They are tadpoles at first, and later change to the adult 

 condition by the absorption of the tail and the development 

 of legs. 



Many examples of peculiar breeding-habits are known. 

 The female of a Brazilian species of tree-frog (Hy'la fa'ber) 

 lays her eggs within a circular wall of mud which she con- 

 structs on the bottom of a shallow pool of water. Within 

 this nursery the tadpoles develop, unless liberated by the 

 rain or other accident. Several species lay their eggs on the 

 leaves of trees above the water, into which the young fall 

 when hatched. The male of the obstetrical toad of Europe 

 (Al'ytes obstet'ricus) winds the eggs around his legs, and, seek- 

 ing a safe place, guards them till they hatch. In a South 

 American species, the famous Surinam toad (Pi 1 pa ameri- 

 ca'na), the eggs are spread by the male over the back of the 

 female, where each egg becomes covered with a growth of 

 skin, forming a pouch with a lid. Here development goes 

 on, and the entire metamorphosis takes place within the 

 egg. In a Chilian species (Rhinoder'ma Darwin'ii) the eggs 

 are transferred by the male to vocal sacs at the side of the 

 mouth, which become greatly developed at the breeding- 

 season. Metamorphosis takes place within these sacs, and 

 the young escape in the adult condition. In half a dozen 



