SNAKES. 9 



rodon guia.nensis,TroschelinSchomburgk's Reise im Brit. Guiana, 

 iii. p. 645. 



Scales in nineteen rows; anterior frontals in direct contact 

 one with the other; one pair of posterior frontals; head and 

 neck blackish brown, with a whitish collar. Posterior maxillary 

 teeth channeled. 



a. Half-grown. Carthagena. From Paris. The specimen agrees 



in all characters with the young specimen described by Du- 

 meril and Bibron, vii. p. 995. Body above scattered with 

 small black points, beneath uniform whitish. In its stomach 

 I found also an Ameiva. Troschel was the first who dis- 

 covered the differences between this species and that de- 

 scribed by Schlegel ; but it appears from Dumeril's descrip- 

 tion, in which both species are again confounded, that 

 Oppel's specimen, the specimen of the ' Ancient Cabinet,' 

 belongs to the South American species, and not to the 

 North American. Therefore we are obliged to restore this 

 species to its first denomination, and to give a new one to 

 the other. 



b. Half-grown : discoloured. Berbice. Presented by Lad}- 



Essex. 



c. Nearly 2' long. America. From Mr. Thomas's Collection. 



Greatly injured. 



3. Rhinostoma cuprkum. 



Scales in fifteen rows; anterior frontals separated one from 

 the other by a long hinder process of the rostral shield, reaching 

 the posterior frontal ; posterior frontals confluent. Head brown, 

 with whitish crown ; body above reddish grey, with two series of 

 brown distinct spots ; beneath uniform whitish. Posterior max- 

 illary teeth smooth. 



a. Adult. Africa. From M. Parzudaki's Collection. 

 b-d. Half-grown and young. South Africa. 



Description.— Head not very distinct from neck; eyes small, 

 pupil round ; mouth moderately cleft ; rostral shield very broad, 

 its breadth nearly erpial to the distance of the eves, bent up- 

 wards, with a sharp convex ridge, reaching the posterior frontal, 

 and separating the anterior ones; anterior frontals triangidar, 

 small ; posterior frontals united, broad, rather narrow, only in one 

 young specimen with a slight longitudinal suture ; vertical large, 

 five-sided, with nearly parallel lateral edges, and an obtuse angle 

 behind; occipitals very small, smaller than vertical, rounded 

 behind ; nasal single, in the centre with the narrow nostril ; one 



