438 Dr. J. E. Gray on several new genera of Reptiles. 



fringed on the side ; outer one webbed at the base ; femoral pores 

 none. 



This tribe is distinguished from Corythophanes and ChamcB- 

 leopsis by the occiput being rounded, and only furnished with 

 a thin, flexible crest of skin, and by the margined toes, instead of 

 having the prolongation of the lateral bony processes of the head, 

 as in those genera. When the Catalogue of the Museum Rep- 

 tiles was published, I only knew three genera ; we have since re- 

 ceived a new one from Mr. Dyson from Honduras, and this col- 

 lection has produced two others from Quibo, on the west coast of 

 America. They may be thus characterized : — 



I, Occiput swollen on each side, with a high crest of compressed 



skin from the back edge of the eyes. 



1, Ptenosaura. 



Back and tail with a series of large, short, compressed scales 

 forming a slight crest ; occiput and crest covered with large thin 

 smooth scales. 



Ptenosaura Seemanni. 



Head (in spirits) blackish ; body brown, blackish speckled ; tail 

 and legs with irregular black cross bands ; angle of mouth and 

 hinder part of chin white ; scales of nose flat, keeled ; of crown 

 and eyebrows small, edged with a series of larger scales ; scales of 

 back small, smooth ; of tail, and especially the outside of legs, 

 larger, keeled ; tail with five series of keeled scales beneath. 



Hab. Quibo. 



Named in honour of Berthold Seemann, Esq., the botanist who 

 accompanied the expedition and brought many zoological speci- 

 mens home. 



II. Occiput swollen, covered with convex scales, the hinder part 



(far behind the eyes) produced into a high crest of compressed 

 skin. 



2. Basiliscus, Gray, Cat. Rep. B. M. 192. 



Back and tail with a high erect crest, supported by bony rays ; 

 occipital crest large, rounded, covered with thin flat polygonal 

 scales. 



B. americanus, Gray, Cat. Rep. B. M. 192. 



Hab. Guiana. 



3. LOPHOSAURA. 



Back and tail with a high erect crest supported by bony rays ; 

 occipital crest small, angular, covered with large keeled scales. 



Lophosaura Goodridgii, n. s. 

 Brown (in spirits) ; head dark ; back and neck with eight 



