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Part II. 

 On the Geographical Distribution of Batrachians. 



In the accounts given of the geographical distribution of animals, 

 we find only a few general statements in which divisions of the earth's 

 surface are characterized for their Batrachio-fauna. The presence of 

 tailed Batrachians in the northern parts of the globe, the scarcity of 

 Batrachians in Africa, gigantic forms between the tropics, and the 

 abundance of Tree-frogs in South America, form the general results of 

 those attempts. The faunas of some provinces were most accurately 

 composed ; but I am not aware that such an attempt has been ex- 

 tended through all the single parts of this suborder. The Batra- 

 chians are better adapted than are Snakes to range over large spaces ; 

 and this is especially observed with some Batrachians of the northern 

 temperate part of the globe. Rana esculenta, Bufo vulgaris, and 

 Hyla arborea are spread over the whole space of Europe and Asia, 

 belonging to the Palsearctic region ; Cantor found them again south 

 of Japan, on the Chinese island of Chusan. Rana temporaria 

 reacb.es beyond even these parts, being equally spread over the tem- 

 perate regions of the New World. But none of the species are to be 

 called cosmopolitan ; and the differences between the different crea- 

 tions are such, that we have not even a true cosmopolitan genus. 

 In looking for genera with the widest range, we may mention Rana, 

 Bufo, and Hyla — the same genera which exhibit also the widest- 

 spread species. 



Bufo is wanting only in Australia ; the most numerous and largest 

 of its species are met with in Tropical America. Rana is entirely 

 wanting in Australia, and represented in the most northern parts of 

 Tropical America by a single species only ; the East Indies and Africa 

 produce most of the species, some from the former region being di- 

 stinguished by their gigantic size, but rivalled by R. mugiens from 

 N. America ; some from the latter region being peculiar on account of 

 very slender and long toes. Hyla is entirely wanting in the iEthio- 

 pian and Indian regions, and in the Arctic regions represented by only 

 a few but widely-spread species, — Tropical America and Australia, on 

 the other hand, producing an exceedingly great number of specific 

 forms. Thus, in speaking of cosmopolitan genera in this paper, I 

 mean those three genera severally, with the restrictions mentioned. 



Such a difference, between the animal life of the New World and 

 that of the Old, as pertains to other parts of the Animal Kingdom, 

 is not to be observed in the Batrachians. Dissimilarity and simi- 

 larity of the Batrachio-fauna depend upon the zones. Paleearctic 

 and Nearctic regions resemble each other more than any third ; the 

 same is the case with Australia and South America ; the ^Ethiopian 

 region exhibits similarities with South America as well as with the 

 East Indies, but more especially with the latter. 



I. Paleearctic Region. 



Characteristic forms. — Pelodytes, Discoglossus, Alytes, Pelobates, 

 Bombinator, Salamandra, Seiranota, Pleurodes, Bradybates, Ellip- 



