530 



KEPOKT OF NATIONAL MU^iEUM, 1898. 



Body niucli depressed and uimsually smooth. Head much depressed, 

 the depth about three-fourths the width, or less, the width more than 

 two thirds the distance from su out to ear; occipital lo/.enge-shaped; 

 vertical lengthened; frontal small, completely embraced by the post- 

 frontals and post-internasals in contact and of about equal size. Two 

 l)airs of postnasals. Inner large supraorbitals usually four, embracing 

 two in their concavity, not three. Fore legs from elbow rather less, 

 hinder from knee rather more, than the distance from snout to ear, 

 which is from one fourth to one-fifth the head and body. The tail is 

 not quite twice the latter distance. There are sixteen longitudinal rows 

 of dorsal scales, the lowest about half that adjacent to it. There are 

 about 48 scales from head to tail above, 55 from chin to anus. The 

 scales are everywhere remarkably smooth ; the carination quite inap- 

 preciable on the back, though 

 each scale is slightly and obso- 

 letely keeled. On the sides 

 this does not extend to the 

 posterior edge, and it is want- 

 ing on the lowest row. All the 

 plates of the head and neck, 

 as well as of the limbs, are 

 smooth or with an inappreci- 

 able trace of carination. 



This species is distinguished 

 from G. burnettii likewise, by 

 having sixteen rows of scales 

 above, by the possession of 

 four postnasals (although some- 

 times the two upper are fused 

 intoonelongone,leavingthree) 

 instead of two. This length- 

 ens the muzzle, which is more 

 depressed. There are only two 

 outer supraorbitals instead of three. The lower row of lateral scales 

 is only half as large as the next instead of nearly equal to it. The 

 carination is much more obsolete, being entirely wanting in the back of 

 the neck, and in some other regions distinctly keeled in G. burnettii. 

 The body is much more depressed. 



This species is of a light reddish, olive brown, the sides for about 

 four or five rows of scales blotched with dusky, nearly black above, 

 and not constituting distinct regular vertical bars; the remnant of a 

 continuous lateral stripe from the snout, and least effaced above. 

 The back has an irregular median series of rounded dusky blotches, 

 sprinkled more distantly elsewhere. There are traces of sixteen or 

 eighteen of the lateral and dorsal dark blotches. The under parts are 

 yellowish white, with a tinge of greenish. The edges of the cephalic 



Fig. 95. 



GERRHONOTUS PRINCIPIS BAIRD and GlRARD. 

 =1. 



Cat. No. 3088, U.S.N. IM. 



