FAMILY, V— CYPRINID^. 527 



fin with few rays, commencing opposite the ventrals. Pectorals horizontal, vnth their outer rays unhramched. Anal 

 short. Scales of moderate size, none on the chest. Lateral-lme complete, continued direct to the centre of the base of 

 the caudal fm. Air-vessel present. 



This Gemis, as illustrated by the single example described, is a connecting link between Homaloptera and 

 Mthus. 



Geographical distribution. — HiU streams and rivers in Bengal and Assam. 



SYNOPSIS OF INDIVIDUAL SPECIES. 



1. Psilorhynchus balitora, D. 9-10, A. 7, L. 1. 33. Reddish-brown, irregularly marked with black. N. E. 

 Bengal and Assam. 



1, Psilorhynchus balitora, Plate CXXI, fig. 7 ; and Plate CXXII, fig. 3. 



Cyprirms balitora, Ham. Buch. Pishes of Ganges, pp. 348, 394 j Cut. and Yal. Hist. Nat. des Poissons, 

 xvi, p. 451. 



Psilorhynchus vaa-iegatus, McClelland, Ind. Gyp. pp. 300, 430, pi. 50, f. 2 (from H. B.'s MSS.). 



Psilorhynchus balitora, Giinther, Catal. vii, p. 343; Day, Jour. As. Society of Bengal, 1871, p. 106, 

 pi. ix, f. 1. 



B. iii, D. 9-10 (y?^), P. 17, V. 9, A. 7 (f), C. 18, L. 1. 36, L. tr. 4|/4|. 



Length of head 5j, of caudal 5, height of body 5 in the total length. Eyes — diameter 4j in the 

 length of head, Ij diameters from end of snout, and also apart. Head rounded, somewhat depressed. A 

 deep cleft extending from the snout to the angle of the mouth. Lips rather thick and reflected from off either 

 jaw. The jaws have sharp edges, but are destitute of any homy covering. Edges of lips not fringed, their surface 

 covered with round hard pores. Some fine pores also on the cheeks and snout. Fins — dorsal commences in 

 advance of the ventrals : pectorals and ventrals nearly horizontal, the outer seven rays of the former and two of 

 the latter unbranched : caudal forked. Scales — 2| rows between the lateral-line and base of the ventral fin. 

 Air-vessel — rather large, divided by a constriction into an anterior and posterior portion, and not enclosed by 

 bone. Colours — reddish-brown, with irregular black blotches forming badly defined bands, in places passing 

 over the back. Three bars on the caudal and some black on the anterior half of the dorsal. 



Habitat. — Hill streams and rapids in N. E. Bengal and Assam. 



Genus, 3 — DiscoGNATHiTS, HeoJcel. 



Ga/rra, Ham. Buch.. Platyca/ra, McClelland: Biscognathichthys et Lissorhynchus, Bleeker : Mayoa, 

 Day. 



Body elongated, suboylindrical. Mouth transverse, semicircular, and inferior; upper and lower lips 

 continuous : no lateral lobes to snout, which projects beyond the mouth. A suctorial dish on the chin, formed on the 

 lower lip, upper lip fringed. Barbels fou/r (Ga/rra, Ham. Buch.) or one pair only at each angle of 'the mouth (Dis- 

 cognatJms, Heckel). Pharyngeal teeth micimate and im, three closely apprommatim,g rows, 2, 4, 5-5, 4, 2, or 5, 3, 1- 

 1, 3, 6. Dorsal flm, with few rays, commencing sUghtly in adva/n,ce of the ventrals, its base scaleless : pectoral 

 horizontal : anal short. Scales of moderate size, no enlarged anal row. Lateral-line continued to the centre of the 

 base of the coAidalfim,. Gill-rakers few, short, and widely set. Air-vessel small. 



Geographical distribution. — Rivers, more especially mountain streams, of Asia and Abyssinia : extending 

 throughput India, Ceylon, and the Tenasserim Provinces. 



SYNOPSIS OP SPECIES. 



1 . Biscognathms lamta, D. 11, A. 7, L. 1. 33-36, 4 barbels. Interorbital space convex. Head 4| to 5| m 

 the total length. A black spot behind gill-opening and geiierally a band along the side. Throughout India, 

 Ceylon, and Tenasserim Provinces, Abyssinia and Aden. 



2. Biscognathus Jerdoni, D. 10, A. 7, L. 1. 36, 4 barbels. Interorbital space concave. Head 6i to 6i in 

 the total length. Wynaad and Bowany rivers in Madras. 



3. Biscognathus modestus, D. 10, A. 6, L. 1. 35, 4 barbels. Interorbital space flat : 5 outer pectoral rays 

 unbranched. Northern India (?). ' , 



1. Discognathus lamta, Plates CXXII, fig. 4, and CXXIII, fig. 1. 



Oyprinus lamta, Ham. Buch. Fish. Ganges, pp. 343, 393 ; Cuv. and Yal. xvi, p. 386. 



Gyprvrms gotyla. Gray and Hardwicke, Ind. Zool. c. fig. ; Cuv. and Val. xvi, p. 387. 



Gnnorhynchus rupeoulus, McClelland, pp. 281, 373, pi. 43, f. 4, 5 ; Cuv. and Val. xvi, p. 467. 



Ohondrostoma mullya, Sykes, Trans. Zool. Soc. ii, p. 359, pi. 62, f. 3. 



Gonorhynchus bimaculatus, brachypterus, and caudatus, McCleU. loc. cit. pp. 281, 283, 373, 374, pi. 43, f. 2. 

 (from H. B.'s MS.) ; Cuv. and Val. xvi, pp. 414, 467. . ^ , ^ on,^ .«o 



Platycara nasuta, McClell. Journ. A. S. of B. vii, p. 947, t. 55, f. 2a and b, and Ind. Cypr. pp. dOO, 428, 

 pi. 57, f. 2. 



