HINTJLIA T A E X I L A T A. 



259 



Although the head is somewhat depressed, the snout is thickish, 

 obtusely conical, protruding slightly beyond the lower jaw. The ros- 

 tral plate is elevated, subtriangular. pointing upwards, and extending to 

 the upper aspect of the head. The nasal plates are large, contiguous 

 upon the middle line of the snout, subtrapezoid in shape, longest in 

 the transverse sense of the head : the nostrils occupying their antero- 

 inferior portion. The odd prefrontal, broader than long, would be 

 hexagonal if its posterior margin were angular, instead of being 

 rounded ; it is contiguous in front to the nasals, sideways to the post- 

 nasals (or anterior lorals, should they so be designated), and behind to 

 the postfrontals and the vertex plate. The latter is quite long, broad, 

 and triangular anteriorly, narrow and tapering towards the parietals, 

 which are rather small, subangular, and narrowest in front. The odd 

 occipital is very small, slender, elongated, arrow-shaped, pointed pos- 

 teriorly. The latero-occipitals are broad and well developed, inclos- 

 ing completely the middle occipital, contiguous sideways to the upper 

 temporal shield, and in front to the supraoculars. There are three 

 well-marked temporal shields ; two lower ones, subrhomboid, resting 

 upon the labial?, and an upper one, larger, subtriangular in shape. 

 The supraoculars are five in number; the third being the largest; the 

 first, which is the smallest, might be considered by others as belong- 

 ing to the supraciliary chain. We observe six in the latter series ; 

 the anterior two largest ; the posterior one equal to the second ; the 

 third, fourth, and fifth very small. The posterior rim of the orbit is 

 formed by five small subequal plates, extending from the commissure 

 between the fifth and sixth labials to the supraciliary chain. A double 

 series of postorbitals, composed each of two small plates, may be ob- 

 served superiorly, in advance of the uppermost temporal shield and 

 exterior angle of the latero-occipital. The anterior rim of the orbit is 

 formed by three plates: an inferior one, situated upon the commissure 

 between the fourth and fifth labials, a middle one, the largest, quad- 

 rangular like the first, and a very small triangular one, contiguous 

 above to the first supraocular. A well-developed, pentagonal loral 

 is next met with, immediately in advance of the middle anteorbital, 

 being contiguous superiorly to the postfrontal and first supraocular. 

 A rather narrow, though elevated postnasal (or anterior loral, it 

 matters not), extends from the second labial to the prefrontal. The 

 upper labials are seven on either side ; the four anterior subquadran- 

 gular, subequal, deeper than long ; the fifth subtrapezoid, longer than 



