300 Mr. Bell on the Box Tortoises. 



generic term Kinosternon to t\ro species, which he' disco v£J'ed in 

 Brazil. 



Like the Emydes^ they may be considered as fresh water 

 Tortoises ; and the general appearance of the shell, the distinct 

 and subpalmated structure of the toes, with the length and sharp- 

 ness of the claws, sanction such a conclusion, even were we un- 

 acquainted with their . general aquatic habits. The species hi- 

 therto confounded under the term Terrapene clausUj and its 

 synonymes, appear indeed at first to be exceptions to this rule, 

 yet although known in America by the common name of Land 

 Tortoise, and having in some measure the appearance and habits 

 of the true Testudines^ we find that their affinities to the rest of 

 tjje -group are sufficiently numerous and important to point out 

 their natural situation amongst them. SchoepfF informs us that 

 the T. clausUy although sometimes found in dry situations, and 

 from the convexity of the shell, &c. not well formed for swimming, 

 yet loves marshy situations ; and M. Say states that it is fond of 

 moisture. There is in fact a natural transition from the Fresh- 

 water to the Land Tortoises of this group, by means of Terrapene 

 Europcea {Tesiudo Europcea^ Auct.), now first transferred to 

 that genus, which, whilst it has somewhat of the flattened form^ 

 and spreading margin of the shell, belonging to the true fluviatile 

 species, yet approaches, in its general structure, the other species 

 of Terrapene, which more nearly approximate to the Land Tor- 

 toises : it is also found to inhabit wet, marshy, or muddy places, 

 rather than the lakes and rivers in which the njore typical Fresh- 

 water species delight. . 



The important character in whichthe species of the group uow 

 under consideration all agree, is the moveable structure of the 

 sternum. In making a few observations upon the different modi- 

 fications of this part, I shall consider the sternum in all of them, 

 as. consisting of three portions or lobes, of which the posteriour 

 consists of that part which is covered by the two posteriour pairs 

 of plates, the middle one by the next pair, and the anteriour by 

 the remaining anteriour plates, which, however, differ in number, 

 according as the foremoiit or gular pair, are either united into one 

 single plate, as in Sternothcerus odoratus, or, on the other hand, 



