68 Records of the Indian Museum. fvior. “vay 
Discognathus adiscus, sp. nov. 
(PIX Mio NOEs pla iene) 
L. 1.36—385 9 D532) Sew ese 
This is a small species of slender habit. The dorsal profile 
from the tip of the snout to behind the dorsal fin is strongly and 
evenly arched; that of the caudal peduncle slightly concave. The 
ventral profile as far as the base of the caudal peduncle is convex. 
The head is of moderate size, its length contained about 5 to 54 
times in the actual total length. It is somewhat flattened above. 
The snout is rounded and smooth. It is shorter than the part of 
the head behind the eye. The nostril is situated nearer the tip of 
the snout than the eye. The eye is large and rather prominent ; 
its length contained about 34 times in the length of the head, and 
a little less than twice in the interorbital breadth; it is not visible 
from below. ‘The pupil is situated near the middle of the head, 
and the upper margin of the eye near the dorsal profile. The 
mouth is large and almost straight. It is situated only a short 
distance behind the tip of the snout. The upper lip is well 
developed, covering the upper jaw, fringed at the margin and 
minutely granular. There are 4 short barbels. The lower lip 
properly so called is only developed at the sides and there is no 
transverse band of specialized structure behind the lower jaw, 
which is fully exposed. The mental disk is very imperfectly 
developed. It consists of a granular pad truncate or subtruncate 
in front, free at the sides, and more or less emarginate, but not 
free, posteriorly. The margins of the opercula meet at an acute 
angle on the mid-ventral line some distance behind it and the 
branchial openings extend well on to the ventral surface. The 
dorsal fin is nearly as high as the body. Its last undivided ray is 
cartilaginous and articulated. The pectorals, which do not nearly 
reach the ventrals, are rather narrow, pointed and distinctly 
shorter than the head. The caudal is long, distinctly lobed and 
with the lobes pointed. The scales are well developed but some- 
what deciduous. They cover the whole of the body. There are 
54 scales between the lateral line and the dorsal, and 4 between 
the former and the ventral. : 
The pharyngeal bones and their teeth closely resemble those 
of D. phryne (v. postea), but the teeth are more slender. 
The dorsal margin is pale bluish grey ; there is a more or less 
distinct bluish mid-lateral streak, running from behind the head to 
the base of the caudal fin. The lower part of the head and sides 
and the ventral surface are yellowish-white. 
Type-specimen, No. 2785 F, Z.S.1. (Ind. Mus.). 
Distribution.—This fish is extremely abundant in small water- 
courses and pools in the plains of Seistan. We obtained speci- 
mens from the following localities :—Nasratabad, irrigation chan- 
nel in Consulate garden; pool in the desert 5 miles south of 
Nasratabad; pools in stream-bed 12 miles north of Nasratabad ; 
channels in the reed-beds of the Hamun-i-Helmand near Lab-i- 
