50 TROPIDONOTUS LEBERIS. 
two posterior orbital, the inferior smaller and quadrilateral, the superior larger 
and crescentic; behind these is a single oblong temporal plate; the inferior wall of 
the orbit is completed by the third and fourth labial, of which plates there are 
eight on each side, all large and nearly quadrilateral. 
The nostrils are lateral near the snout, and open a little upwards. The eyes 
are large, the pupil dusky, and the iris golden, with a few black specks. ‘The 
neck is contracted, and covered with small sub-hexagonal carinated scales. 
The body is elongated, rather slender, and covered above with large hexagonal, 
strongly carinated scales, slightly notched at their posterior extremity, and with 
broad plates below. The tail is long, slender, and slightly sub-triangular and 
compressed at the sides. 
Cotour. The superior surface of the head is olive-brown; the lips are straw- 
colour. The body above is olive-brown, with three longitudinal dusky lines; the 
belly is pale yellow, with four dusky longitudinal, parallel lines on the plates; 
those near the lateral extremities are largest, those near the centre of the 
abdomen smaller. The tail is coloured above like the back, though the lines 
disappear long before they have reached the tip; below, the lateral lines are 
continued for some distance, the central ones giving only a waving clouded 
appearance at the junction of the sub-caudal bifid plates. 
Dimensions. Length of head, 1 inch; length of body, 19 inches; length of tail, 
7 inches: total length, 27 inches. Dr. Green informs me that he has specimens 
in his possession much larger than the dimensions above given. In the specimen 
here described there were 143 abdominal plates, with the anal double, and 70 
bifid plates under the tail. 
Hasrts. Not much is known of the habits of the Tropidonotus leberis. Mr. 
Peale, however, informs me that it is a water-snake; and this might almost 
