302 



REPORT ON FISHES. I'ART i: COBITIDAE 



bladder 411 species of the genus Garra* in which the torrential species possess a similar type 

 of posterior chamber. This process of retrogression is much more pronounced in A'^. hsiit- 

 schoiicnsis (Text-figure IE). 



The type of bladder found in N. pal>illo-labiatus (Text-figure IC), N. strainiiii (Hora 

 1*^130, Te.xt-figure 7) and A', actiticcplialus (Ilora 1930, Text-figure 9) is rciuarkable in so 

 far as the free bladder is situated very far back in the abdominal cavity and is connected with 

 the bilobed anterior portion and the oesophagus ])y means of a long tul^e. In the case of 

 A'^. acuticcphalits I surnu'scd tliat the pfisition of the liladder was ])riil)ably due to its burrow- 



Fir.uRE 2. Form of caudal fin in llie torrential species of A^c/iiac/ii'/jii from Western Tibet, a: Ncmachilus 

 gracilis Day X2; b: Nentachilus stolicskae (Steind.). X2J^; c: Nemachilus tcnuicauda (Steind.). X3/^; 

 d: Nemachilus microps (Steind.). X 2}/i. 



ing habits. This hypothesis receives sujjport frimi tlic fad tliat in Psi'udapocryplrs luncco- 

 Itiliis, an eel-like burrowing Gobioid fish, the bladder has shifted backwards to the anal 

 region, though in the young stages, when the fish leads a pelagic life, the bladder occupies 

 almost the whole of the abdominal cavity.' 



In air-breathing fishes of the families Anabantidac and Aphiccphalidac, the air-bladder 

 extends into the caudal region as far as the base of the caudal fin. The utility of this remark- 

 able modification has been explained l)y me in another place (Hora, Cur. Sci. Ill, p]). 336- 

 338, 1935). It seems probable, however, that the backward position of the bladder in 

 A^. papillo-IabJatus, N. strauchii and N. acuticcphalus enables them to lie horizontally at the 

 bottom and obviates any tendency of the anterior part to rise. This is merely a tentative sug- 

 gestion as no observations have yet Ijeen made on the mode of life oi these fishes. 



'Hora, Rcc. hid. Mus. XXII, p. 646 (1921). 

 'Hora, Current Science III, p. 336 (1935). 



