12. GONTOCEPHALTTS. 285 



of the orbit. Tail very strongly compTessedj with serrated edge 

 above ; caudal scales perfectly smooth, except the two inferior series, 

 which are enlarged and strongly keeled; length of the tail once and 

 a half that of head and body, Olive-brown above, with a series of 

 darker spots on each side of the back ; tail with regular dark 

 annuh. 



Total length 331 miUim. 



Head 38 



Width of head 26 



Body 93 



Fore limb 75 



Hind limb 105 



Tail 200 



Borneo. 

 a. cJ. Sarawak. A. Everett, Esq. [0.]. 



2. Gonyocephalus chamseleontiuus. 



Gonyocephalus chameleontina, Gray, Cat. p. 238. 

 Iguana chamseleontiiia, Laur. Syn. Rept. p. 47. 

 Lacerta superoiliosa, Shaw, Zool. iii. p. 220, pi. Ixviii. 

 Agama gigantea, Kuhl, Beiir. Zool. Vergl. Anat. p. 106. 

 Lophyius tigrinus, Dmn. Sf Bibr. iv. p. 421, pL xli. (part.) ; Schleg. 



Bijdr. tot de Dierk. i. p. 5, pi. i. 

 Galeotes lophyrus, Sehleg. Ahhild. p. 73, pi. xxiii. 



Head high, with strongly elevated projecting supraciliary borders 

 forming an angle posteriorly ; snout as long as the diameter of the 

 orbit, ending in a small rounded hump in the adult female ; tym- 

 panum much smaller than the eye-opening ; upper head-scales small, 

 subequal, smooth ; sides of the head with small subgranular scales, 

 with a few enlarged subcorneal ones on the temple ; ten to twelve 

 upper, and eleven to fourteen lower labials. Gular sac well de- 

 veloped, with serrated anterior edge ; gular scales much smaller 

 than ventrals, smooth. Body very strongly compressed. Nuchal 

 and dorsal crests continuous ; the former begins on a line with the 

 posterior border of the orbit, and is formed of long compressed spines 

 with three rows of smaller ones at the base ; its height in the adult 

 equals the length of the snout ; the dorsal crest rapidly decreases in 

 height, and is soon reduced to a feebly serrated ridge. Dorsal 

 scales very small and smooth, with the points directed upwards, 

 with a few scattered enlarged ones ; ventral scales much larger, 

 smooth. Limbs above with subequal smooth or feebly keeled scales ; 

 fourth finger a little longer than third ; the adpressed hind Umb 

 reaches the posterior border of the orbit. Tail strongly compressed, 

 without crest, with keeled slightly serrated upper edge ; upper 

 caudal scales smooth or feebly keeled, lower larger and strongly 

 keeled ; length of the tail not quite' twice that of head and body. 

 Olive or greenish above, with dark reticulation which may form 

 more or less distinct bands across the back ; tail with regular dark 

 annuli. 



