ZOOLOGICAL INFORMATION. 



Geographical distribution of the Chelones — The Chelones are principally dis- 

 tributed in the warmer regions of the world, and near to the tropics, but they 

 extend also to many portions of the temperate zones, reaching in the northern 

 hemisphere to the 50° and beyond it, though in the southern they scarcely pass 

 the 35° of S. latitude. It has been observed that the sea tortoises prefer the 

 warmer climates, and some species are peculiar to certain parallels. The Che- 

 Ionia imbricata delights in the intertropical seas, although it appears not to have 

 been found either upon the coast of Africa or on the great Indian Ocean. The 

 Ch. viridis, on the contrary, frequents all the seas of the torrid zone ; but the 

 Ch. cephalos, which is generally met with in the northern hemisphere, advan- 

 cing to the 48°, is common in the western part of the world, while it is rare in 

 the eastern, and appears only accidentally to frequent the coasts of countries 

 situated beyond the equator. Spargis, again, may be considered cosmopolite, 

 and is found either indigenously or accidentally in most of the seas frequented 

 by the marine tortoises. 



Of all countries, America produces the greatest number of the Chelones which 

 are comprehended in the genus Emys, but this vast continent at the same time 

 maintains only a single species of the genus Trionyx, confined apparently to the 

 southern parts of the United States, while the only land tortoise of the new 

 world Test, tabulata, extends from South Carolina over the greater part of inter- 

 tropical America ; we are ignorant, however, whether this species, common to 

 many of the Antilles, has been originally indigenous to them, or has been im- 

 ported. We might also presume this to be the case with the Indian tortoise, 

 whichis at this time distributed over the western coasts of N. and S. America from 

 California to Chili, and we might even have suspected, that this large tortoise 

 had been naturalized upon the Galapago isles of the Pacific, although at so great 

 a distance from its true country if the early Spanish navigators had not met with 

 it in abundance on these solitary and deserted islands. We have already re- 

 marked, that North America produced only one species of Trionyx, Tr. ferox, and 

 that this country, on the contrary, is remarkably rich in species of the genus 

 Emys. All the species agree, however, nearly with the last, or they may be con- 

 sidered as tortoises inhabiting equally the land or water. One of them, E. ser- 

 pentina, spread over most of the provinces of the United States, is peculiarly 

 aquatic in its habits, and evidently forms the passage to the genus Trionyx; an- 

 other, on the contrary, E. clausa, common from Hudson's bay to the Floridas, 

 approaches in its manners to ,the land tortoises, which it seems intended to ally 

 to the genus it has been placed in from its own structure. Other species, as E. 

 punctata and odorata, approach the manners of the land division, though in a less 

 degree. They are common in the United States, but the first does not exist in 

 the southern provinces, which the second inhabits, and has been found as far 

 south as the river Alvarado, in Mexico. The other Emydes of North America 

 are, E. picta, Mullenbergii and centrata, species more peculiar to the northern 

 states, reaching even to Canada ; also E. serrata, reticularia and geographica, which 



