214 



Records of the Indian Museum. 



[VOL. XIX, 



and the other in Garra ' with Discognathus as an intermediate 

 form. 



I believe that the evolution of the Homalopteridae has 

 occurred along the line of the Cobitidae of which we may take 

 Nemachilus as a central genus. Among the Homalopteridae, a 

 Bornean genus Glaniopsis , Boulenger/ is verj^ much like Nemachilus, 



Primitive Cyprinoidea 



as can be inferred from its figure in Beaufort and Max Weber's 

 Fishes of the Iiido- Australian Archipelago. This peculiar Homa- 

 lopterid genus possesses a pair of barbels between the two nostrils 

 and we know that a similar pair of barbels occurs in an Indian 

 loach Nemachilus evezardi} Of the three Indian genera of this 

 famil}', Homaloptera is the most primitive, Bhavania has evolved 

 independently from the same stock in South India and Balitora, 

 the most highly specialized genus, has also been independently 

 evolved from the original primitive stock. The extreme form of 

 specialisation is reached in another (Bornean) genus Gastromyzon* 

 Giinther ; but the discussion of the forms outside India is beyond 

 the scope of the present paper. 



The relationships of the various genera discussed in this 

 paper are graphically represented on the opposite figure. 



i Annandale and Hora, Rec. Ind. Mus. XVIII, p. 162. 



■^ Boulenger, Ann. Mag. Nat. Hist. (7) IV, p. 228 (1899). 



^ Annandale, Rec. Ind. Mus. XVI, p. 114 (1919). 



4 Giinther, Ajzn. Mai^. Nat. Hist. (4) XIV, p. 454 (1874). 



