REPTILIA. } 287 
Cd 
meatus; nostrils anterior; tongue fleshy, depressed, and thick. The cloaca is 
situated under the tail, with the orifice rounded and puckered. The male 
organ is simple. 
Fam. 1. Testudinida. The family first to be considered embraces spe- 
cies which are exclusively terrestrial. They are known by their high-arched 
carapace, their full ossification, the complete investment of all the toes by a 
common skin, forming a true club-foot, on the exterior of which are to be 
found the blunt nails. ‘The jaws are naked; the tympanum visible; the eyes 
lateral, with the lower eyelid higher than the upper. The tongue also is 
papillose. The four generic forms are, Ainirys, Homopus, Pyxis, and 
Testudo. But one of these genera, Testudo, is found in North America, 
where it is represented by a single species, 7. polyphemus, or the gopher. 
This animal is found in Georgia and Florida, in sandy districts, where it 
excavates holes in the ground which much impede the movements of horse- 
men. Another species, 7°. elephantopus, is found in great numbers in the 
Gallapagos Islands, were they average 60lbs. in weight. ‘They are eagerly 
sought for by the crews of vessels, and when captured serve for fresh 
meat,.and may be kept in the hold of a ship for a year without food or 
drink. One species, 7. graeca (pl. 81, fig. 40), is found in the South 
of Europe; while 7°. geometrica (pl. 81, fig. 39, and pl. 90, fig. 13) lives in 
the East Indies. 
Fam. 2. Emydide. In this family, the feet are more perfectly formed 
than in the last, the toes being five im number and movable, most generally 
united by a membrane or palmated. The mandibles are usually horny, 
trenchant, and naked. ‘The tympanum is visible, and the eyelids are of equal 
height. The tongue, of nearly equal thickness throughout, is smooth at the 
surface, but presenting longitudinal folds. In most species the shell is con- 
siderably depressed. 
This extensive family presents two sub-divisions or sub-families, whose dis- 
tinguishing features are to be found in the shape of the head, in the position 
of the eyes, and in the manner in which the head and neck are retracted 
within the shell. 
In the first sub-family, the Cryptoderes, the head is conical, sometimes as 
as high as broad; the eyes are lateral. The neck is short, thick, cylindrical, 
invested by a loose non-adherent skin. When the head is retracted the 
neck assumes an 8 shape, and both are nearly, if not entirely, concealed by 
the anterior margin of the shell, or by the loose skin of the neck. The 
most striking anatomical difference between the two sub-families is that in 
this the pelvis is attached to the carapace by a cartilaginous symphysis, and 
not at all to the plastron, this permittmg a certain freedom of movement ; 
while in the second sub-family, the pelvis is immovably attached to both cara- 
pace and plastron. 
The first genus to be referred to among the Cryptoderes is Cistudo, 
which includes the common land tortoise (C. clausa) of the United States. 
Here the carapace is very high and arched, while the lower shell or plas- 
tron is divided into two pieces by a hinge, which enables them to shut 
close against the upper shell, and thus completely to inclose the entire 
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