KINOSTERNONPENNSYLVANICUM. 25 



which allows of certain motions. The supplemental plates are triangular, the 

 posterior very large. 



The head is large and rather pointed at the snout; the nostrils are anterior. 

 The eyes are large, the pupil dark, the iris dark gray, with a very narrow border 

 of light gray around the pupil. The upper and lower jaws are very strong, and 

 both are furnished with a hook in front. The neck is long, rather slender; the 

 skin above is covered with small warts, and the throat with larger. There are 

 four very remarkable warts about the lower jaw; two of these are placed at the 

 chin, and two under the angle of the mouth. 



The anterior extremities are short, rounded, and covered with a warty skin, 

 and having two transverse rows of large scales in front, with some large scales 

 near the tarsus behind; there are five fingers, palmate, each furnished with a 

 short nail. The posterior extremities are elongated, much flattened at the tarsus, 

 and covered with a minute warty skin, and eight or ten large scales near the 

 ankle and tarsus; there are five toes, fully palmate, the four internal ones only are 

 furnished with nails. The tail is very short, thick at the root, pointed and horny 

 at the tip. 



Colour. The shell is of a universal dusky brown colour above. The sternum 

 varies a good deal; sometimes it is dusky, with a yellowish tinge, and has darker 

 lines at the junction of the plates; at others it almost approaches a dark chestnut 

 colour. 



The head is nearly black above, and dusky at the sides, freckled with minute 

 yellowish spots. The jaws are horn colour, with delicate waving dusky lines. 

 The neck is dusky above; the chin and throat are of dirty yellow, with the larger 

 warts of brighter yellow. 



The extremities and tail are dusky above, and clouded or dirty yellowish-white 

 below. 



Vol. III.— 4 



