EMYSTERRAPIN. 15 



are furnished with nails. The tail is short, thick at the root, but small and pointed 

 at the tip, and covered above with a row of scales, which gives it a sharp ridge. 



Colour. The colour of this animal varies a good deal more perhaps than in 

 that of any other Emys; generally speaking, it is dusky brown, though frequently 

 it is greenish, or dark olive colour. The marginal plates are all yellowish beneath, 

 each with a ring of dark gray colour; in the centre of this ring occurs frequently 

 a dark spot: sometimes we find two or three of these rings placed one within the 

 other, with intermediate yellow lines, and a yellow spot in the middle. 



The sternum also varies in colour; it is generally yellowish, marked with con- 

 centric strise and dusky lines; seldom more than two on a plate, forming squares, 

 which are sometimes single, sometimes double, the inner line always following the 

 figure of the outer; at other times the sternum is entirely yellow. 



The crown of the head is sometimes very dark; sometimes greenish, or olive. 

 The jaws are horn colour, mottled with dark spots, or crossed by transverse dark 

 lines or bars. The side of the head, the neck, as well as the extremities, are dusky 

 or greenish-white, studded with innumerable black dots; these are sometimes so 

 disposed as to give a marbled appearance to the skin. 



Dimensions. Length of shell, 7^ inches; length of sternum, 7 inches 2 lines; 

 elevation, 2 inches 10 lines. 7 



Habits. The Emys terrapin lives in salt water and in salt marshes, where it 

 hybernates; far from these it is never seen. It is a timid animal, easily disturbed, 

 and hiding itself on the least alarm. It swims with great rapidity, and, unlike its 

 tribe in general, moves quickly even on land. 



Geographical Distribution. This is a widely extended animal, abounding in 

 marshy places from New York to Florida. I have no doubt that it exists along 

 the northern shores of the Gulf of Mexico, although I have no positive evidence 



