FRESH-WATER FISHES OF SIAM, OR THAILAND 361 



The first reference to the fish under its scientific name was in two 

 papers published by Bleeker in 1865. Bleeker may have had access 

 to Bocourt's manuscript or at any rate had knowledge of Bocourt's 

 contemplated use of the name Pangasius larnaudii for a new species. 



It is believed that Pangasius hurgini Fowler (1937) will prove to 

 be P. larnaudii^ which although one of the commonest members of the 

 genus in the Bangkok region was not noticed in any of Fowler's papers. 

 P. hurgini was described and is known from a single specimen, 23,2 

 cm. long, from Bangkok, and was stated by its describer to be related 

 P. taeniwrus and P. sutchi "but differs from both in coloration, and 

 especially in the presence of the gray black large post-humeral blotch." 

 Each caudal lobe has a broad black median band which is connected 

 with its fellow by an extension of the color across the base of the fin. 

 The maxillary barbels do not reach the base of the pectoral fin. The 

 vomero-palatine teeth are in a curved band on each side, with a 

 median space but with no apparent division of the band into vomerine 

 and palatine parts. The branched anal rays number 27, as against 

 at least 25 in P. lai'noMdii. The reduced number of gill rakers — 5 + 7 

 on the first arch in P. burglni — is met with also in P. larnaudii; a 

 specimen from Bangkok of the same size as the type of P. hurgini has 

 4+9 gill rakers. In all important characters there seems to be essen- 

 tial agreement between the two forms. 



The vernacular name always given to this fish is pla tepo, and this 

 name is never applied to any other species. 



PANGASIUS PLEUROTAENIUS Sauvage 



Pnngasms pleurotaefiia Sauvage, 1878b, p. 235 (Laos, Indo-China) ; 1883b, p. 154 

 (Menam Chao Phya). 



Describing this fish from Cambodian Laos in 1878 and redescribing 

 and figuring it from Cambodia in 1881, Sauvage (1883b) noted it 

 again in a collection obtained in the Menam Chao Phya b}' Har- 

 mand. This is the only record of the species for Thailand, unless 

 P. sutchi Fowler should prove to be the same. The principal charac- 

 ters on which the species was based are the separation of the bands of 

 vomerine teeth and their union with the palatine teeth, maxillary 

 barbels reaching opercles, 36 to 40 anal rays, back and upper part of 

 head black, and a straight black band extending along the side of the 

 body. Sauvage placed the fish in the same group as P. larnaudii 

 because of similarity of dentition, 



A length of 16 cm. is given. 



PANGASIUS SUTCHI Fowler 

 Pangasius sutchi Fowleb, 1937, p. 141, figs. 27-29 (Bangkok). 



Described from four specimens, 13.3 to 16.3 cm. long, from the 

 Menam Chao Phya at Bangkok, this species is represented as strikingly 



