THE TONGUELESS FROGS 



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on each side of the body. Each family is represented by a single genus, respec- 

 tively confined to tropical Africa and tropical South America. 



The spur-toed frogs (Xenopus) of which there are three species from 

 tropical Africa, are characterized as a family by the presence of teeth 

 in the upper jaw; while they are further distinguished by the circular 

 pupil of the eye, the absence of an external tympanic membrane to the ear, the free 

 front-toes, and the webbed hind-foot, in which each of the three inner toes is fur- 



Spur-Toed 

 Frog 



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SMOOTH SPUR -TOED FROG AND ITS TADPOLE. 

 (Natural size.) 



nished with a sharp, spur-like nail. The smooth spur-toed frog (X. lavis}, which 

 is the species here represented, has a wide geographical distribution, ranging from 

 Abyssinia to the Cape; and is characterized by its smooth skin, marked round the 

 body with more or less distinctly defined tube-like lines. In color it is dark brown 

 above, and whitish beneath, some individuals being uniform, while others are 

 spotted with brown on the under surface. The spur-toed frogs are exclusively 

 aquatic, pursuing even their prey beneath the surface of the water, and capturing 



