1847.] Malayan Peninsula and Islands. (341 



spots and a narrow ring. The eyelids are covered with very mi- 

 nute polygonal, tubercular scales. Each tarsus with a double row 

 of scales, the inner one of small, polygonal, tubercular ; the outer 

 one of rhombic, flat, with the angles overlapping, so as to give the 

 free margin a toothed appearance. The tympanum is large cir- 

 cular. The skin of the throat is very lax, forming a compressed 

 pouch, the anterior margin of which is slightly toothed, owing to the 

 series of scales overlapping each other But there is during life no 

 trace of any "crossfold behind, extending up the front of the shoul- 

 ders." The scales of the neck and back are very minute, rhombic, or 

 sub-rectangular, smooth, increasing in size and becoming imbricate on 

 the sides, abdomen, limbs and throat. On the neck is a high arched, 

 toothed crest, composed of 26 large ensiform scales, the 13 anterior 

 gradually increasing in length, the rest decreasing. The base of the 

 crest is supported by two parallel, slightly arched, series of rectangular 

 scales, much larger than those of the rest of the body, but those 

 of the upper series double the size of those of the inferior. The 

 dorsal crest commences at a short interval a little behind the shoul- 

 ders. In shape and component parts it resembles the former, but is 

 double the extent, consisting of 45 scales, all of which however are 

 inferior in height to those of the cervical crest, which, as well as the 

 somewhat lower, sloping level, renders the dorsal crest less conspi- 

 cuous than the former. The skin is somewhat lax on the sides of the 

 body, leaving the ribs visible. The tail is very much compressed, 

 attenuated, elongated. Its sides are covered with rather large, smooth 

 imbricate, rhombic scales. The anterior third of the upper margin is 

 toothed, composed of a single row of large, gradually decreasing, 

 sharply keeled scales. The other two thirds are covered by two rows 

 of keeled scales, thus giving the posterior part of the tail a bidentated 

 appearance. The lower surface of the tail is covered by two series 

 of large, gradually decreasing, imbricate, keeled scales, giving it a 

 bidentated appearance. The limbs are slender ; the anterior little more 

 than half the length of the posterior, and the toes very short. The 

 posterior 4th toe is excessively long. The palms and soles are covered 

 with minute, pointed, rough scales ; the toes above and beneath with 

 sharply keeled, imbricate, rhombic scales. The claws are large, tren- 

 chant, curved. 



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