356 



AMERICAN TESTUDINATA. 



Part II. 



3. EvEMYDOiD.E. Differ chiefly from the preceding by the great width and flat- 

 ness of the plastron, the narrowness of the bridge wliich unites the plastron and 

 carapace, and the movability of the plastron, at its junction with the carapace, 

 and upon itself, owing to a transverse articulation across its middle. The feet 

 are webbed. 



4. CleiMMYDOId.e. Their chief peculiarity consists in their more arched though 

 elongated form, and the more compact structure of their feet, the front and hind 

 pairs of Avhich are more nearly equal, and the toes united by a smaller web. 

 They are less aquatic, and generally smaller than the preceding. 



5. CiSTUDiNiNA. The body is remarkably short and high, slightly oblong, and 

 almost round. The plastron, which is movable upon itself and upon the carar 

 pace, as in the EvemydoidiB, is also connected with the carapace by a narrow 

 bridge ; but the feet are very different, the toes, as in the Testudinina, being nearly 

 free of web. Their habits are completely terrestrial. 



SECTION IX. 



THE FAMILY OF TESTUDININA. 



The land Turtles are now generally considered as a primary division among 

 the Testudinata. J. E. Gray was the first to separate them, under the name of 

 Testudinidce, as a distinct family,^ which was soon afterwards adopted by Fitzin- 

 ger^ and Th. Bell.^ In 1828, Ritgen changed the name of the family to Cher- 

 sochelones.* In 1830, Wagler^ proposed the name of Tylopodes for this same 

 family, which he considers, however, only as a tribe of the one family Testudines, 

 to which he refers all the Testudinata. In 1832, Wiegmann*' considers them 

 again as a family, which he calls Chersina?, while Canino,^ considering them only 



1 Ann. of Phil. 1825, vol. 10. In all Ins later 

 writings, Gray retains the name of Testutlinidfe ; but 

 as Testudo is a Latin noun, it does not admit of a 

 patronymic ending. The family name of the land 

 Turtles should, therefore, be written Testudinina. 



^ Fitzinger, Neue Classification, etc., I82G, writes 

 the family name Testudinoidaj ; but in 183G, Syst. 

 Anord. d. Schildkr., he adopts Wagler's name, Tylo- 

 podes, changing it to Tylopoda. 



" Bell (Th.), in Zool. Journ. 1828, vol. 3, p. 

 419 and 513. He also writes the name Testudinidiie. 



* Nov. Act. Acad. Nat. Cur. 1828, vol. 14. 



* Wagler, Natiirl. System d. Amphibien, 1830. 

 « Handb. d. Zool. 1832. 



' Saggio An. Vert. 1832 ; compare also Chelon. 

 Tab. Anal. 183G. The family to which Canino refers 

 the Testudinina is called by him Testudinida?, and is 

 not to be confounded with the Testudinida?, Gray, as 

 it embraces, besides the land Turtles, all the other 

 Amyda;, to the exclusion of the Trionychidae only, 

 which he separates as another family coequal with the 

 Testudinida;. 



