1922.] S. L. Hora : Central Asiatic Cobitidae. 69 



Diplophysa strauchii, Hi river flowing- into Lake Balkasli. 



labiatus, Urrljar river flowing into Ala-kul. 



;, intermedins, Lake Dalai-nor. 



,, nasal is, ,, 



,, costata, ,, 



,, dalaicus, ,, 



knvgessana, Kinges River. 



,, papilloso-labiata, J nidus. 



nticrophthal inns, Chaini. 



Of the nine species enumerated above the first two are from 

 Eastern Turkestan, the next four from Lake Dalai-nor, which is 

 situated in the lake basin of Mongolia, and the remaining three 

 from the Tarim river-system which ultimately drains into lake 

 Lob-nor. It is significant, that all the Cobitid fishes known from 

 Lake Dalai-nor belong to the genus Diplophysa. A new species 

 of this genus described here was obtained by Capt. Kennedy and 

 Capt. Stewart in a small stream flowing into Rham-tso, a lake of 

 considerable dimensions at an altitude of 14,700 ft. in Eastern 

 Tibet. 



It will thus be seen that the genus is known from Eastern 

 Turkestan and Mongolia on the one hand and from Rham-tso in 

 Eastern Tibet on the other. This apparently discontinuous dis- 

 tribution may be accounted for by the fact that very little is at 

 present known of the ichthyology of the intermediate region. 



There is yet another possibility which may explain the distri- 

 bution of this genus. It is possible that the genus is polyphyletic 

 in origin, because the character of the bladder on which it is 

 solely based, may have originated on more than one occasion in 

 response to life in deep waters which necessitated some hydrostatic 

 mechanism. 



The genus Diplophysa is represented by two species in the 

 collection of the Indian Museum, one of which is new to science. 



Diplophysa papilloso-labiata Kessler. 



1878. Diplophysa papilloso-labiata, Kessler, Bull. Acad. St. Pc'ters- 



bourg XXV, p. 299.. j 



1878. Diplophysa papilloso-labiata, Kessler, Mel. biol. X, p. 257. 

 1888. Nemachilus strauchii var. papilloso-labiatus, Herzenstein, 



IViss. Res. Przeivalski Central As. Reis., Zool . Ill (2), p. 50, 



pi. vi, fig. 5. 

 1910. Diplophysa (Nemachilus) strauchii papilloso-labiata, Zug- 



mayer, Zool. Zahrb. Syst. XXIX, p. 297. 



This is the only species of the genus Diplophysa collected by 

 Dr. Stoliczka. There are seven specimens in our collection and 

 they are labelled as having come from Yarkand, probably from 

 the Yarkand river which forms a part of the Tarim river-system. 

 Of the seven specimens four are males and the rest females. The 

 species exhibits a well-marked sexual dimorphism. 



The free air-bladder is not constricted in the middle and lies 

 almost in the middle of the abdominal cavity. In my dissections 

 I have not been able to find any pneumatic duct. 



