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NORTH AMERICAN BATRACHIA AND REPTILIA. 
Family TESTUDINIDJE. 
Genus Testudo, Linn. 
126. T. Carolina, Linn. Gopher Turtle. Above brownish; 
head almpst black; beneath yellow; fore limbs large and strong; 
hind ones short and rounded; plastron projecting beyond the 
carapace in front. Austroriparian region. 
Order CROCODILIA. 
Family CROCODILIDJE. 
Head depressed, elongated; nostrils approximated at end of 
muzzle; tongue fleshy, adherent; teeth in a single row; body 
depressed ; with solid, carinated shields on back; tail compressed 
laterally; presacral vertebrae procoelian. 
Nasals entering into formation of nasal aperture; teeth 
unequal. 
a . Muzzle broad; sides of head subparallel; forehead 
divided longitudinally by a ridge; fourth pair of man- 
dibular teeth received in pits in sides of upper jaw. 
Alligator. 
b. Muzzle narrow, head tapering; fourth pair of mandib- 
ular teeth received into grooves in edges of upper jaw. 
Crocodilus. 
Genus Alligator, Cuv. 
127. A. mississippiensis , Daud. Common Alligator. Nu- 
chal plates four, separate from cervical; on back eight longitu- 
dinal series of quadrilateral and strongly tuberculo-carinated 
plates; flanks covered by nine or ten rows of smaller, smooth, 
rhomboidal plates; beneath, the smooth square plates are arranged 
in transverse and longitudinal rows; above dusky brown or 
black in adult; in young barred with yellow; beneath yellowish, 
somewhat dusky. Austroriparian region. 
Genus Crocodilus, Cuv. 
128. C. americanus , Seba. Floridan Crocodile. Muzzle 
elongated; nuchal plates four to two; cervicals six; dorsal plates 
in four longitudinal series; vertebral large, regular, broader than 
long; lateral series scattered, irregularly hexagonal; head and 
back of male rough, of female comparatively smooth; the former 
leaden black above; almost or quite destitute of yellow; the lat- 
ter uniformly mottled with black and yellow; beneath pale yellow, 
darker on sides, with tine irregular streaks and spots of black. 
Floridan district. 
