152 SAURIA. 



PHYSIGNATHUS, Cuv. 



Tympanum naked; the upper parts covered with minute granular scales 

 of equal size, arranged in transverse series ; throat tubercular ; ventral scales 

 smooth ; head without any spines. A crest on the back and tail ; a fold 

 across the throat. Tail compressed, covered with keeled scales, those at 

 its lower side rather broader than long, strongly keeled. A series of pores 

 on the inner side of the femur. 



Head tetrahedral, covered above with minute granular scales, with some larger scales along 

 the canthus rostralis ; snout obtuse ; nostril lateral, in the middle of a small shield ; eyebrows 

 not prominent ; eyes of moderate size ; eyelid scaly. Teeth compressed, triangular ; a pair of 

 small canine teeth in each jaw. Tongue slightly notched. Labial shields numerous; a series 

 of shields along each side of the throat ; skin of the throat lax, covered with tubercular scales ; 

 the tubercles on the side of the throat are unequal in size, larger ones being mixed between 

 smaller ones, and three or four in the middle between angle of the mouth and shoulder 

 being the largest, conically prominent. A fold across the throat, none before the shoulder. 

 Trunk of the adult compressed, and elevated into a sharp ridge ; the body of the young is 

 more rounded. The scales are uniformly small, granular, disposed in transverse series. 

 Adult specimens with a crest, composed of more or less elongate lobes according to the age 

 of the individual ; the crest is more or less distinctly interrupted above the fore and hind 

 legs. Belly covered with small, smooth, rhombic scales. The tail is very long, and strongly 

 compressed; the crest of the back is continued for some distance, and gradually passes into 

 a double, minutely serrated ridge ; the sides of the tail are covered with keeled rhombic 

 scales, smaller than those at its lower siu-face, where they are strongly keeled. Legs rather 

 long ; the hind toes are slightly fringed along the outer edge ; the scales at their lower side 

 are not keeled. 



The lizards of this genus attain to a larger size than the other Indian Agamidce, and 

 approach the Iguanidce in general habit. Nothing is known of their habits. 



Only two species are known : — 



Six or seven intralabial shields Ph. cochinchinemis. 



Eleven intralabial shields Ph. mentager. 



