656 Records of the Indian Museum. [Vol. XXII, 



than to the base oC caudal fin. There are nine branched and two 

 unbranched rays in it and the first branched ray is the longest. The 

 ventrals originate before the fourth branched dorsal ray and extend 

 to beyond the anal opening. The caudal fin is deeply emarginate, 

 the lower lobe is much the longer. The colour of the body and 

 head in spirit is uniformly dark brown with the exception of the 

 ventral surface which is dirty-white. The colour of the upper 

 and the lower surfaces of the paired fins corresponds to the colour 

 of the dorsal and the ventral surfaces of the body respective!}-. 

 There are black spots at the bases of the dorsal fin rays and the 

 membrane between the rays is also blackened. 



Extreme modification of the air-bladder occurs in this species. 

 Both the chambers are minute and possess thick walls. There is 

 a thick fibrous coat covering the bladder and fixing it firmly to the 

 body-wall. The following are the measurements of the bladder in 

 the adult specimen : — 



Length of anterior chamber ... 2*5 nun. 



,, ,, posterior ,. ... ... 3'5 mm. 



Greatest diameter of anterior chamber 2"5 mm. 



,, posterior ,, .. I'5 mm. 



In the young specimens, the liead and body is not greath' 

 depressed and the air bladder is comparatively larger. The two 

 lobes of the caudal fin are unequal and an indistinct proboscis is 

 present on the snout. The head is fairly lotig and bluntly pointed, 

 and the eye in some examples is not wholly in the posterior half 

 of the head. The upper surface is dark and the under surface of 

 the head and belly is white. The fins are white and at the base of 

 the dorsal fin there are small black spots ; sometimes a big black 

 blotch is present before the base of the caudal fin In an example 

 from Manipur one of the rostral barbels is furcaxe. 



Annandale (.see Chaudhuri, 1913) identified the Abor specimen 

 from Siyom River as Discognathus lamia subsp. nasutits (McClel- 

 land). 



Distribution. — McClelland recorded it from the Khasi and the 

 Mishmi Hill tracts. Specimens of this species have now been 

 obtained in the Abor Hills and in the Manipur Valley, Assam. I 

 refer numerous 3'oung specimens from Sikkim to this species with 

 .some doubt. 



