176 A new genus of Serpents, &(t, 



I have named this genus Acontias.* 



Sp. I. Acontias leucostoma. 



White-mouthed Acontias, generally known by the name of 

 Cotton-mouthed Snake. 



Caput erectum depressum. Apertura inter oculos et nares 

 in utroque latere. Scuta in vertice prolongata novem. Pos- 

 terior pars capitis squamis ovatis sub-carinatis tecta. Supra 

 fuscus cum maculis irregulariter rhomboidalibus, colore nigro 

 fuscoque variegato, abdomine maculate griseo et fusee. 

 Scutis abdominalibus 135. 

 Scutis subcaudalibus ad basem 21. 

 Scutellis sub apicem caudae 21, quarum 4to, 5to, et 6to, 

 sunt integra. 

 Squamis dorsalibus ovatis subcarinatis cum duobus punctis 

 flavis pseudo-metallicis ad basem. 



Telis perforatis veneniferis duobus in maxilla superiore. 



The total length is - - - - 26 inches. 



Tail .--.-- si- 



Head 1^, of which the larger plates cover f 

 Breadth of the head - - - if 



Diameter of the neck _ - _ | 



Tail a little more than \ of its whole length. 

 The head is of an oval form, the upper lip forming an angle 

 of about 85 deg. with the upper part of the head, which is flat, 

 and separated from the lip by a distinct edge. The fore part 

 of the head, as is seen in the engraving, (plate V.) is covered 

 with nine large plates ; the two foremost are quadrants of a 

 circle, the two next being irregular pentagons ; the three suc- 

 ceeding, the middle one of which is a hexagon, having one 



* Acontias, from axovriaj, a word used by Nicander and other ancients 

 for Snakes, is an unmeaning denomination, but is better than names de- 

 signating characters not applicable to the whole genus. 



