34 TRIGOXOCEPHALUS PISCIVORUS. 



Description. The head is triangular and very large, covered with plates in 

 front and on the vertex, and with small scales posteriorly. The vertical plate is 

 regularly pentagonal, with an acute angle behind; the superior orbital are 

 irregularly quadrilateral, narrowest within, broadest without, and projecting far 

 over the eve, so as to give it a threatening appearance; the occipital plates are 

 reo-ularly pentagonal, with acute angles forward; posterior to them is a transverse 

 row of four smaller plates; the frontal are pentagonal, large, with their outer 

 margins rounded; the anterior frontal smaller and triangular, with the bases 

 rounded and pointed forward, and the apices backwards and inwards; the rostral 

 plate is nearly quadrilateral, a little larger below. There are two nasal plates; 

 the anterior is quadrilateral, a little excavated posteriorly; the posterior is 

 irregularly quadrilateral, concave in front, to complete the nostril. There are 

 two anterior orbital plates; the superior very large, the inferior smaller, making 

 the posterior wall of the pit between the eye and nostril, which is completed in 

 front and below by the second labial, and a small plate resting on the third labial. 

 The posterior orbital plates are three in number, and nearly of the same size; the 

 inferior makes part of the inferior wall of the orbit, which is completed by the 

 third labial plate. 



The nostrils are large, lateral, and near the snout; a very deep pit exists 

 midway between them and the eye, but on a loA\'er plane; the upper jaw is 

 covered with seven labial plates. The eye is large, though it does not appear 

 so at first view, from the projection of the superior orbital plate; the pupil is 

 elhptical, dark and vertical; the upper half of the iris bright golden, the inferior 

 half, black; the neck is greatly contracted; the body elongated, very robust and 

 thick, even to the tail, where it contracts suddenly; it is covered with carinatcd 

 scales, to those adjoining the plates; those above are most strongly carinated. 

 The abdomen is covered with very broad plates; the tail is short, thick, convex, 

 and terminates in a horny point, having carinated scales above, and plates and 

 scales below. 



Colour. The head is dark brown above, with a yellowish line from the snout 



