44. TRIGONOCEPHALUS ATRO-FUSCUS. 
orbital plates, rhomboidal, of which the superior is largest, and forms most of the 
orbit behind. The upper jaw is covered with eight quadrilateral, labial plates. 
The nostrils are large, lateral, and near the snout. The eye is rather large, the 
pupil elliptical, black, and the iris grey, tinged with yellow. The posterior part of 
the head is covered with small hexagonal and not carinated scales, in which it 
differs from the Trigonocephalus piscivorus. The neck is greatly contracted, and 
the body, though elongated, is thick to the tail, which is short, cylindrical, slender, 
and terminates in a horny tip. The superior surface of the back and tail is 
covered by elongated, oval, and deeply carinated scales, with small points at their 
base; the abdominal plates are large. 
Corour. The upper part of the head is dark brown, bordered with grey, which 
becomes lighter behind the eyes, with a dark longitudinal spot reaching from the 
orbit to the tympanal bones; the upper lip is white, terminating near the tip in 
grey. The colour of the body is dusky, variegated with brown spots of smoky- 
grey, broadest on the back, and disappear entirely near the tail, which is black. 
The throat is marked with black and white, the latter colour predominating; the 
belly is also irregularly spotted with black and white, darkest towards the tail, 
and in all parts the white is minutely dotted with black. 
Drensions. Length of head, 13 inches; breadth of head, 12 inches; length of 
body, 20 inches; length of tail, 35 inches: total length, 25 inches. In the specimen 
here described, there were 133 abdominal plates, and 25 sub-caudal, near the base 
of the tail, and 18 bifid plates near its apex. 
Hasirs. The Trigonocephalus atro-fuscus is always found on dry land, in the 
pine barrens and similar places, and never in water or swamps. “It is a vicious 
animal, and its bite is very dangerous.” 
GrocrarnicaL Distrisution. This reptile has as yet only been observed in 
Tennessee. 
