242 APPENDIX. — REPTILES. 



species of that genus ; and Dumeril's description of Elaps de- 

 cussatus being in accordance with our specimen, and both speci- 

 mens coming from the North-western part of South America, 

 both species may prove to be identical, provided Elaps decussatus 

 has not the dentition of Elaps. 



Body elongate, cylindrical ; head rather narrow, of equal width, 

 not distinct from neck ; tail rather short, not distinct from trunk, 

 ending in a blunt conical scale ; muzzle rounded, blunt ; eye 

 small. Rostral shield moderate, rounded, reaching to the surface 

 of forehead, with an obtuse angle behind and a transverse groove 

 beneath ; anterior frontals much smaller than posterior ones ; 

 vertical shield five-sided, broader than long, with a rather convex 

 front-side, with the lateral sides shortest and convergent, and 

 with a right angle behind ; occipitals moderate, rounded behind ; 

 superciliary small ; nostril between two shields ; one anterior 

 ocular, smaller than posterior nasal, and far distant from vertical 

 shield; one semilunar posterior ocular in contact with a single 

 temporal shield, behind which are three other ones ; six upper 

 labials, the third and fourth of which come into the orbit ; the 

 first four are nearly equal in size, the fifth as large as the two 

 preceding together, the sixth equal to the fifth ; the first pair of 

 lower labials form together a suture behind the medial one ; one 

 pair of chin-shields behind. Scales moderate, in fifteen rows, 

 those of the vertebral series somewhat irregular on the hinder 

 part of the body ; anal entire ; subcaudals two-rowed. Upper 

 parts of head black, with a yellow narrow band across the front 

 edge of the posterior frontals ; another band across the occiput ; 

 under side of the head, two anterior labials and temple yellow. 

 Ground-colour of trunk orange-coloured, but the black rings 

 encircling the trunk are so confluent on the back, as nearly to 

 suppress the yellow rings ; the latter are formed b}' scales, which 

 liave a black central streak and a black tip, and only yellow 

 outer edges ; moreover each black band is crossed by another 

 yellow variegated narrow band, which does not extend on the 

 belly. On the belly the black and yellow bands are more equal, 

 each occupying three or four ventral plates. The ground-colour 

 of the tail is bright red, and the black rings are smaller. There 

 are on each side of the upper jaw seven strongly-curved small 

 teeth of nearly equal length, none of which are grooved. Length 

 of cleft of mouth f" ; length of tail 2" ; total length 15". 



Page 13. Add to Riiardosoma a third new species. 



8. Rhabdosoma oxycephalum. 



Upper labials five, the third and fourth coming into the orbit ; 

 the firth forming a long suture with the occipital shield; one 



