190 THE INFANCY OF ANIMALS 



environment would have been tenantless so far as the 

 Amphibia are concerned. 



A good illustration of this is furnished by a larval frog 

 found in sandy streams and pools of water from 2,000 to 

 3,000 feet above the level of the sea. Unlike all other 

 tadpoles, they float vertically, and have the fleshy lips of 

 the mouth answering to the lips of the tadpole of the 

 common frog produced into a large trumpet-shaped funnel 

 which acts as a surface float. The inside of this funnel is 

 beset with a radiating series of litlle horny teeth, and the 

 whole apparatus is apparently used for scraping the 

 under-surface of the leaves of water-plants in search of 

 food. Obviously in such out-of-the-way situations vegeta- 

 tion is scarce and food is not plentiful, but one wonders 

 what started the modification of the fleshy lips in the new 

 direction, enabling this particular species alone to obtain 

 a living. Needless to say, it is little known save in 

 museums, and hence has no name in everyday speech, 

 but it is known in scientific works as Megalofhrys 

 montana. 



More mysterious, and much more extraordinary, is the 

 case of the South American Paradoxical Frog (Pseudis 

 ■paradoxa). The adult is entirely aquatic in habits, and 

 most beautifully coloured, displaying wonderful tints of 

 bronze, bright green and black above, while underneath it 

 is a bright yellow spotted and barred with brown. Finally, 

 be it noted, it does not exceed two and a half inches in 

 length. Yet, in the tadpole stage it not only presents a 

 peculiar shape, but attains a monstrous size. This at 

 any rate is no exaggeration of speech for a tadpole which 

 attains nearly a foot in length at its maximum of growth ! 

 Of this bulk the head and trunk represent only a fraction 

 over three inches, the rest is made up of an enormous tail, 



