in the Collection of the British Museum. 19 



Cm'onella poecilolcemus. 



This species resembles externally Liophis regincB and L. 

 tceniurus ; but the dentition is syncranterian, the three or four 

 posterior teeth gradually increasing in length. The head is 

 rather narrow and elongate. The anterior frontals two-thirds 

 the size of posterior ; vertical narrow and elongate, but shorter 

 than the occipitals, which are rounded behind. Loreal as high 

 as long ; one anteocular, not reaching the vertical ; two post- 

 oculars. Eight upper labials, the fourth and fifth below the 

 orbit. Temporals 1 + 2, the foremost very elongate. Six 

 lower labials are in contact with the chin-shields. Scales in 

 seventeen series, without pores. Ventrals 159 ; anal divided ; 

 subcaudals 67. Upper parts nearly uniform blackish ; a faint 

 reddish-brown streak along each side of the back of the tail 

 and hind part of the trunk, bordered below by an indistinct 

 blackish streak. Lower parts white chequered with black, 

 the black spots being less numerous on the posterior part of 

 the trunk, and disappearing entirely on the subcaudals ; they 

 are more numerous and confluent on the anterior half of the 

 abdomen, the lower side of the head being yellowish with 

 rounded black spots. A yellow band along the upper labials, 

 continued on the side of the throat. 



Two specimens were collected by Mr. Bartlett on the Upper 

 Amazons. Total length \b\ inches, tail 3^ inches. 



Liophis purpurans. 



Ahlabes pttrpu7-ans, D. & B. p. 312. 



Diadophis purpurans, Jan, Iconogr. livr. 16, pi. 5. fig. 5. 



This snake is very closely allied to L. cohella, Merremii^&c, 

 with regard to its general habit, pholidosis, and coloration. I 

 would also describe the dentition rather as diacranterian than 

 as isodont, the two posterior teeth being decidedly larger than 

 the preceding, and separated from them by a slight yet con- 

 spicuous interspace. 



Tachymenis hitorquata. 



Rostral low, scarcely extending to the upper surface of the 

 head ; anterior frontals transverse, one fourth the size of pos- 

 terior ; vertical very broad, subtriangular, scarcely longer than 

 broad, and somewhat shorter than the occipitals, which are 

 obtusely rounded behind. Nostril between two nasals ; loreal 

 large ; prceorhital single, widening above, and in contact with 

 the vertical ; two postoculars. Eight upper labials, the fourth 

 and fifth entering the orbit. Temporals 2 + 3. Scales in 

 oblique rows, in nineteen series. Ventrals 195 ; anal entire ; 

 subcaudals 97. Each scale yellow, with a black margin ; 



2* 



