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



Barbus oatesii, Boulenger. 



i8(|^ Earbii!. oatesii. Boulenger, Ann. Mag. IVa/. Hist, (d) Xll, i>. .'01. 



Annandale' regarded this species as being synonymous with 

 Barbus sarana caudimarginatus , Blyth, after comparing his speci- 

 mens from the Inle Lake with a cotype of Boulenger's oatesii and 

 as a result of his examination of a series of specimens of B.. sarana 

 from India and Burma in the collection of the Indian ^luseum. In 

 identifying my specimens I have referred to the same sources, and 

 am convinced after a careful examination of the large series, that 

 B. oatesii is a distinct species and that Annandale's own specimens 

 undoubtedly belong to the true B. sarana c audi mar ginatus. 



The most important difference between the two species is in 

 the structure of the dorsal spine In B. oatesii it is strong and 

 very strongly serrated, with 12 to 19 serrations on each margin of 

 its posterior border. The serrations along the two margins of the 

 spine are very close together and become longer and stronger 

 from below upwards. In B. sarana caudimarginatus the spine is 

 strong but finel}' serrated onty in its upper half or two-thirds, the 

 serrations are subequal. Along the posterior aspect, the spine is 

 deeply grooved and the serrae are situated on its margins ; their 

 number is indefinite. The colour of the two species is also differ- 

 ent. In both the forms, however, the opercular cleft has a black 

 edge, which probably led to the confusion of the two species. In 

 B. oatesii, as Boulenger observed, each scale is edged with black. 

 This condition is not so well-marked in the cotype examined by 

 Annandale, because the colour has become very faint on account 

 of the specimen having been in spirit for over a quarter of a cen- 

 tury. There can be no doubt regarding the colouration of the 

 young specimens collected by me in Thaubal stream about a mile 

 from Phaidai. Under a lens the black edge is seen to consist of 

 minute black dots which are more closely aggregated along the 

 anterior border of the scale. 



The caudal fin is also different in the two species. In B. 

 oatesii it is long and deeply notched, the lower lobe being broader 

 and longer. In B. sarana caudimarginatus the caudal fin is rela- 

 tively shorter in length, and is not so deeply notched. The two 

 lobes are equal in length. 



The proportions are also different in the two species. 



In young specimens the length of the caudal fin, the depth of 

 the body and the length of the head are almost equal and are 

 contained 4^ — 4f times in the total length. The caudal fin is very 

 brittle and is broken in most specimens. The following are the 

 measurements of two complete young individuals : — 



Total length including caudal 

 Length of caudal 

 Depth of body 

 Length of head 



I .Annandale, Rec. liid. Miis.. .\I\' 



