AMPHIBIA. 309 



is the common bull-frog (R. Catesbiana). Among the more im- 

 portant remaining genera of Ranid* are Rhacophorus (with Polype- 

 dates, according to Boulenger), whose thirty or more species inhabit 

 Japan, the Philippines, Southeast Asia, India (with Ceylon), and 

 Madagascar; Txalus, with about twenty -five species, restricted to 

 the East Indies ; and Rappia, with a nearly equal number of species, 

 inhabiting tropical Africa. 



The tree-frogs (Hylidse), with upwards of one hundred and sixty 

 species, find their greatest development in the Neotropical region, 

 which contains somewhat more than one hundred species. The 

 genus Hyla itself is represented by nearly ninety species, or by 

 nearly three-fourths of all the known forms. The species of the 

 North American fauna are comprised in the genera Hyla, Acris, 

 and Chorophilus. Temperate Eurasia has but a solitary representa- 

 tive of the family, the common tree-frog (Hyla arborea), which, in 

 its several varietal forms, is distributed from Great Britain and the 

 Canary Islands to Japan. Hyla Chinensis and H. annectens, the 

 latter from North India, are the only other Asiatic species. The 

 genus Hyla is wanting in the Ethiopian realm, but is represented 

 by several species on the continent of Australia, whose amphibian 

 fauna is made up almost exclusively of the families Cystignathidse 

 (about twenty species), Bufonidce (six species), and Hylidse (eleven 

 species — Hyla and Hylella). 



Scarcely inferior in point of specific development to the tree- 

 frogs are the Cystignathidaj, whose one hundred and fifty or more 

 species are almost entirely restricted to Australia (with Tasmania) 

 and South America, a few species penetrating northward into Mexico 

 and the West Indies, and three or four into the Southern and Western 

 United States (Florida, Texas, California). The family may, there- 

 fore, be said to be distinctive of the Southern Hemis})here. The 

 most abundantly represented of its numerous genera is Hylodes 

 (forty-five species, tropical America), peeping-frogs, many of whose 

 species partake of the habit of the common tree-frogs. Collectively 

 the species are very broadly distributed, and penetrate far beyond the 

 region of elevated temperatures. Hylodes leptopus, about the most 

 southerly of all known species of frog, descends to the Strait of 

 Magellan, while H. Whymperi was obtained by Mr. Whymper on 

 the slopes of Chimborazo at an altitude of 13,200 feet. Paludicola 

 marmorata (Leiuperus viridis), a member of the same family, was 



