12. SONTOCEPHALTJB. 291 



greater than the length of the snout ; it is composed of a few large 

 lanceolate spines directed backwards, implanted on a strong dermal 

 fold covered with small keeled scales ; dorsal crest formed of spines 

 similar to the nuchals. Dorsal scales small, keeled, with the 

 points turned upwards and backwards, intermixed with scattered 

 enlarged ones forming more or less regular transverse series ; 

 ventral scales twice as large as dorsals, keeled. Limbs above 

 with subequal keeled scales. Tail strongly compressed, with a very- 

 high crest of lanceolate scales ; caudal scales feebly keeled except 

 inferiorly ; tail once and a half the length of head and body. Eeddish- 

 brown above, with indistinct darker spots ; dorsal crest oUve. 



Total length 650 miUim. 



Head 75 „ 



Body 145 „ 



Fore limb 105 „ 



Hind limb 193 ,. 



Tail 330 ' 



N" ew Guinea. 



13. Gonyocephalus tuber culatus. 



Tiaris tuberculatus, Gfunth. Proo. Zool. Soe. 1872, p. 698, pi. xxxviii. 



Snout as long as the diameter of the orbit ; canthus rostraUs and 

 supracUiary edge sharp, projecting ; tympanum as large as the eye- 

 opening; occiput concave ; upper head-scales small, strongly keeled ; 

 twelve upper and ten lower labials. Gular sac rather small, without 

 serrated anterior edge ; gular scales smooth, smaller than ventrals ; 

 a large subcorneal tubercle below the tympanum. Nuchal crest 

 not continuous with dorsal, its greatest height somewhat exceeding 

 the length of the snout ; it is composed of lanceolate spines directed 

 backwards, very small anteriorly, gradually becoming very large ; these 

 spines implanted on a dermal fold covered on each side with three or 

 four rows of keeled pointed scales directed upwards ; dorsal crest 

 formed of large lanceolate spines like the posterior nuchals, with a 

 basal series of smaller feebly keeled scales. Dorsal scales smooth or 

 very feebly keeled, with the points directed upwards, intermixed 

 with irregularly scattered enlarged ones ; ventral scales moderately 

 large, smooth. Limbs above with subequal feebly keeled scales ; 

 fourth finger slightly longer than third ; the adpressed hind limb 

 reaches the eye. TaU. very strongly compressed, with an upper crest 

 composed of triangular lobes gradually decreasing in size towards 

 the end ; caudal scales large, the upper feebly, the lower strongly 

 keeled ; length of the tail not twice that of head and body. Olive, 

 with very indistinct brown spots; gular fold black. 



Total length 375 miUim. 



Head 37 „ 



Width of head 24 „ 



Body 103 „ 



v2 



