GONYOCEPHALUS 135 



Description of type. — (From Boulenger.) "Snout as long 

 as the diameter of the orbit; canthus rostralis and supraciliary 

 edge projecting; tympanum smaller than the eye-opening; upper 

 head-scales small, keeled, slightly enlarged on the supraorbital 

 region; scattered conical scales on the back of the head and on 

 the temple; ten or eleven upper and eleven or thirteen lower 

 labials. Gular sac small, vi^ithout serrated anterior edge; gular 

 scales strongly keeled, smaller than ventrals, intermixed with a 

 few enlarged ones on the sides. Nuchal crest formed of lan- 

 ceolate spines with smaller keeled ones at the base; its height 

 equals two thirds the length of the snout; dorsal crest not con- 

 tinuous with, and lower than, the nuchal, gradually decreasing in 

 height. Dorsal scales very small, smooth or indistinctly keeled, 

 with the points directed upwards and backwards ; enlarged scales 

 on the flanks, forming irregular vertical series ; numerous small 

 tubercles on the nape; ventral scales of moderate size, keeled. 

 Limbs with unequal keeled scales ; third and fourth fingers equal ; 

 the adpressed hind limb reaches the nostril. Tail strongly com- 

 pressed, with slightly serrated upper edge; caudal scales all 

 keeled, largest interiorly; length of the tail twice that of head 

 and body." 



Color, — *Tale olive above, the enlarged tubercles and two cross 

 bands, one on the nape, the other between the shoulders, whitish ; 

 tail with regular dark-brown annuli ; limbs with rather indistinct 

 dark cross bands; throat with very indistinct dark lines." 



Measurements of Gonyocephalus interruptus Boulenger, 



mm. 



Total length 280 



Head 29 



Width of head 22 



Body 66 



Foreleg 53 



Hind leg „ 85 



Tail 185 



Remarks. — The type of this species was collected in Mindanao 

 and presented to the British Museum by G. Taylor. 



The differences between this form and Gonyocephalus semperl 

 do not appear to be very marked. The specimens which I ob- 

 tained in Mindanao were referred to G. semperi on the character 

 of the row of scales parallel to the dorsal crest. Among them 

 is one in which most of the scales of this row are missing but it 

 agrees in most, even minute, details with the other forms. 

 Peters's description is very meager. I am convinced that the 

 variations in the skull will be eventually used in differentiating 

 these species. 



