350 Mr. G. A. Boulenger on new Snakes. 
widely forked. Lateral line ascending above the pectoral, 
thence descending in a long reversed curve on the lower 
half of the side, becoming straight posteriorly. 
A single species, Z. amza, Linn. 
CAMPOGRAMMA, gen. nov. 
Differs from the preceding genus in the rounded scales, 
the jaws with a single series of rather strong conical teeth, 
the anal shorter than the soft dorsal, the pectoral of moderate. 
length and falcate, and the lateral line forming a long even 
curve auteriorly, straight posteriorly. 
A single species, C. vadigo, Risso. 
XXXIII.—Descriptions of new Snakes in the Collection of 
the British Museum. By G. A. BOULENGER, F.R.S. 
Tretanorhinus tentatus. 
Head small, narrow; eye small. Nasals in contact with 
each other behind the rostral; a pair of small internasals, 
followed by three preefrontals, the median of which is penta- 
gonal and twice as long as broad ; frontal once and a half 
as long as broad, as long as its distance from the rostral, 
shorter than the parietals; loreal a little longer than deep; 
two pre- and two postoculars; temporals 1+2 or 2+3; 
8 upper labials, fourth entering the eye; 4 or 5 lower labials 
in contact with the anterior chin-shields; posterior chin- 
shields longer than the anterior and separated from each 
other by scales. Scales in 21 rows, striated and keeled. 
Ventrals 168; anal divided ; subcaudals 81. Greyish olive, 
with a broad, white lateral band occupying the three outer 
series of scales; this band bordered above by a blackish 
streak extending to the tip of the snout and passing through 
the eye; sides of snout and lower surface of head blackish, 
dotted with white ; a dark median streak on the occiput and 
nape, reappearing on the tail; three ill-defined dark streaks 
along the belly. 
Total length 570 millim. ; tail 130. 
A single female specimen from the Rio Sapayo, N.W. 
Ecuador, altitude 450 feet. 
Opisthotropis lateralis. 
Snout short, rounded, much depressed, feebly projecting 
beyond the mouth.’ Rostral a little broader than deep, well 
