A MONOGRAPH OF THE SHA-SNAKES (HYDROPHIINA),. 199 
Again, I do not share Mr. Boulenger’s opinion with regard to the snake figured 
by Schlegel (Phys. Serp., 1837, plate xviii, figs. 6.and 7) which he considers fasciata 
(Schneider). The specimen is so faithfully depicted that one can count 21 rows of 
scales in the neck (fasciata has 25 to 31). It appears to me to agree perfectly with 
gracilis (Shaw). 
I find the posterior maxillary teeth in this species grooved in at least three well- 
grown specimens. 
gracilis (Shaw) shares with cantorvis (Giinther), a combination of characters which 
occurs in these two species alone amongst Distive. The portion of the rostral visible 
above is nearly equal to or even exceeds the length of the internasal suture ; the fourth 
infralabial touches two scales only behind, and the ventrals in the major part of the 
posterior half of the body are grooved or divided in the median line, so that each is 
represented by a pair of pentagons with apposed bases. The commissure of the 
mouth seen in profile resembles the italic letter /. (Not well shown in figure 10). 
Some of these characters are suggested or approached in others of the very slender- 
necked species, viz., obscura (Daudin), fasciata (Schneid.) and neglecta (Wall), but the 
ventrals are quite peculiar to gracilis and cantoris. 
Description.—Body anteriorly three-tenths to one-fourth the greatest depth. The 
last measurement was from a gravid female. 
The head shields show great constancy. 
Rostral,—the portion visible above, three-fourths to greater than the internasal | 
suture. Praefrontals,—touch the second supralabial (five exceptions on one or both 
sides). Postoculars,—one. Temporals,—one large anterior succeeded by 
another even larger shield, the anterior touching the fifth and sixth supralabials. 
Supralabials,—6, not subject to division. Infralabials,—4, the last 
touching two scales only behind; the suture between the first longer than that 
between the anterior sublinguais. Marginals,—none. Sublinguals,—two pairs, 
the fellows of each in contact. Costals,—anterior I9 (17 in two, 18 in three, and 
21 in one), midbody 27 to 31, posterior 27 to 35; the anterior imbricate, the posterior 
juxtaposed. Ventrals,—225 to 298; entire anteriorly and about twice the breadth 
of the last costral, row divided or furrowed in the median line in the posterior half of 
the body. Colour,—in the young the head is quite black. The body is surrounded 
with from 42 to 61 annuli, usually dilated, and often more or less confluent vertebrally , 
and ventrally especially in the forebody. With age the rings may lose definition, 
or become much obscured especially ventrally, and the head often assumes a much 
lighter hue. 
Habitat.—All the specimens I have examined were procured from shores between 
the Persian Gulf and Mergui on the Tenasserim Coast. 
DISTIRA CANTORIS (Gunther). 
Liopala fasciata, Gray in Zool. Misc., 1842, p. 60. 
Hydrophis fasciata, Gray, Cat., 1849, p. 50, spec. C. 
cantoris, Gunther, Rept. Brit. Ind., 1864, p. 374, pl. xxv, fig. V. 
1) 
