REPORT ON FISHES. PART 1 : COBITIDAE 309 



Ncmachiliis gracilis Day 



1876. Neiuachcilus gracilis, Day, Proc. Zool. Soc. London, p. 798. 



1878. Neiuachcilus gracilis, Day, Sci. Res. 2nd Yarkand Miss. Ichthyology, p. 16, pi. iv, fig. 5. 



1878. Nemacheilus gracilis, Day, Fish. India, p. 621. 



1889. Ncmachilus gracilis. Day, Faun. Brit. hid. Fisli. I, p. 257. 



1898. Neniachilus stoUczkae, Alcock {ncc Steindachner), Rep. Nat. Hist. Pamir Bound. Comui., 



p. 38. 



1922. Ncmachilus gracilis, Hora, Rec. Ind. Mus. XXIV, p. 74. 



1933. Ncmachilus gracilis, Hora, Rcc. Ind. Mus. XXXV, p. 189. 



1935. Ncmachilus gracilis, Hora & Mukerji, in \'isser's Karakornni, I. p. 430, pi. iv, fig. 2. 



Ncmachilus gracilis appears to be one of the commonest loach of the Indus River and 

 its range extends from very high altitudes to as low down as Attock in the North-Western 

 Frontier Province. Few specimens of the species were also obtained by tlie Netherland 

 Karakorum Expedition from the Karakash Valley. In the collection of the Yale North 

 India Expedition, A^. gracilis is represented from the following localities. The specimens 

 were collected during May to July, 1932. 



Stream 1 mile of IJras, ca 10,100 ft. (K76). 6 specimens (young). 



Dras, (-(( 10,144 ft. (K 77). 22 specimens (9 3 — 13 9 ). 



Spring below Kargil, ca 8,790 ft. (K81). 1 specimen ( <5 ). 



Above Leh, ca 15,000 ft. (L25). 3 specimens (young). 



Between Tangt.se and Mugleh, ca 13,700 ft. (L37). 1 specimen ( S ). 



Kyam rivulet, ca 15,500 ft. (L59). 1 specimen (young). 



Kyam, a pool below camp, ca 15,500 ft. (L60). 1 specimen { S )■ 



Yalapuk, ca 13,521 ft. (L79). 2 specimens (young). 



Sta-rtsak-puk Tso, ca 1-1,889 ft. 4 specimens (young). 



The above distribution shows that the species frecjuents ptiols in the course of streams, 

 springs and lakes for breeding purposes as young specimens were collected from such 

 localities. It is essentially a torrential species of wide range. 



N. gracilis is readily distinguisiied by the fact that, as a rule, the ventrals do not extend 

 as far as the anal opening, the eye is almost in the middle of the head and the ventrals 

 cnnnnence in advance of the dorsal. The structure nf the biwer lip is also characteristic 

 of the species. 



The air-bladder is of the usual reduced type, consisting of two lateral chambers enclosed 

 in bone. The alimentary canal is simple and not much convoluted; its length is about three- 

 fifths of the total length of the fish. The food consists of insect larvae, mostly free-living 

 Dijitera and Trichi>])tera, and of the slime encrusting rocks and stones in rajjid current. 

 The small, fan-shaped, horizimtal ])aired fins, reduced air-bladder and its food .strongly 

 suggest that the lish lives in very fast currents. Young specimens were collected from 

 underneath slimes in a ris'ulet. 



Ill the mature females, the ovaries occu])y almost the whole of the abdonu'nal cavity 

 and even the alimentary canal is flattened out. The eggs are of a fairly large size (diameter 

 about 1.25 mm.). 



