1919. | N. ANNANDALE: Fish from India aud Persia. 71 
beneath the lateral line are poorly developed. The lateral line is 
conspicuous. 
The pharyngeal bones are broad and very convex. They each 
bear twelve teeth, but the second tooth of the outer row is very 
short, though broad, and almost hidden by the others. The 
formula appears to be 6.3.3/3.3.6, but the teeth are very closely 
congregated and the rows difficult to distinguish. The teeth are 
fairly long and slender but shorter than those of D. adiscus, 
sharply pointed (except the second of the outer row) and slightly 
retroverted at the tip, which is obliquely truncate. 
The colouration varies with the environment, but the scales, 
the upper part of the cheeks, the operculum and the dorsal surface 
of the head and body are always minutely speckled with black, 
and the specks are always more numerous on the back and on the 
top of the head than elsewhere. In individuals from very clear 
water they are so numerous as to give these regions a blackish 
colour. Larger black spots are sometimes present on the upper 
part of the sides, and a narrow blackish vertical bar can usually be 
distinguished on the distal end of the caudal peduncle. The ven- 
tral surface and the lower part of the head are white. The iris is 
speckled like the scales. The fins are colourless. In the young 
there is a bluish mid-lateral streak running along the body. 
Type-specimen, No 2787 F., Z.S.I. (Ind. Mus ) (from Seistan). 
Distribution.—This species is very abundant in the hill 
country of Baluchistan at altitudes between 5,000 and 6,000 feet. 
A single specimen was taken by Mr. S. W. Kemp and myself, with 
many of D. adiscus, in an irrigation channel at Nasratabad, Seistan. 
Habits.—D. adiscus is gregarious and lives as a rule among 
algae on the bottom of slow-running water-channels and pools. In 
the outflow of the Kushdil Khan reservoir in the Pishin district 
north of Quetta large numbers were observed opposite the places 
where water flowed in from underground sources. The weather 
was very cold at the time and this water was warmer than that 
which came from the reservoir. ‘The fish were feeding on a green 
filamentous alga. 
The species seems, as already stated, to be closely related to 
D. variabilis, Heckel, and is doubtless the one referred to by Zug- 
mayer! as intermediate between that form and D.lamta. It is 
almost certainly identical with the D. variabilis mentioned in the 
editorial note prefixed to Tate Regan’s account of fish from 
Seistan in Journ. As. Soc. Bengal, (n.s.) I, p. 8 (1906). 
SEcTION II.—Grvoup of Discognathus lamta. 
1838. Platycara, McClelland, Fourn. As. Soc. Bengal, VII, (2), p- 944- 
This group is certainly more highly developed than that of D. 
variabilis, The mental disk is always relatively large and is a 
1 Zugmayer, Abh. Bayerisch. Ak. Wiss. Math.-phys. Klasse XXVI (6), 
p- 24(1913). These specimens were from the Pishin River in northern Baluchistan. 
There are two Pishins in Baluchistan, the one north of Quetta and one, referred 
