40 TRIGONOCEPHALUS CONTORTRIX. 
inferior orbital plate is single, long, narrow and semicircular; there are two 
anterior orbital, the upper quadrilateral, the lower makes the superior wall of the 
pit between the eye and the nostril, which is completed below by the second 
labial plate, and by a small plate that rests on the third labial. The margin of 
the upper jaw is covered with seven quadrilateral plates. 
The nostrils are large, lateral, and placed near the snout. The eyes are large, 
but do not at first appear so from the projection of the superior orbital plates; 
the pupil is elliptical, vertical and dark; the iris bright golden, with a tinge of red. 
The neck is greatly contracted and covered with smooth scales; the body is 
elongated, but thick to near the tail, and is covered above with rhomboidal 
scales, carinated, except those of the lower rows, which are smooth and larger. 
The abdomen is covered with plates, the last one of which is very large; the tail 
is short, thick, conical, and ends in a horny tip. 
Corour. The head is a delicate light hazel-nut brown above, with the labial 
plates whitish; the ground colour of the whole animal, neck, body and tail, is of 
the same delicate hue, lighter on the sides, where the scales are beautifully 
freckled with small dark spots. Behind the occiput begins a series of transverse 
bars of dark brown, continued to near the extremity of the tail; these bars are 
contracted along the vertebral line, but are broader and bifurcated on the flanks. 
These bars are lightest on the back, darker at the sides, with their anterior and 
posterior margins bordered with brown. The under surface of the whole animal 
is flesh coloured, freckled with minute points of dark brown, and a series of 
sub-round dark coloured spots on the abdominal plates near the extremities; 
these ascend to include a scale or two on the flanks, and are so disposed that one 
spot corresponds to the poimt of bifurcation of the transverse dorsal bars, and 
another to the space between them; all these spots terminate at the tail, which is 
flesh colour below. 
Dimensions. Length of head, 1 inch 2 lines; breadth of head, 11 lines; length 
of body, 21 inches; length of tail, 3} inches; greatest circumference of body, 33 
