FRESH- WATER FISHES OF STAM, OR THAILAND 77 



common and conspicuous in the commercial catch. The only record 

 for the eastern region is a typical specimen taken February 16, 1927, 

 in the Nam Pong, a tributary of the Mekong, at Pong. 



While the fish reaches a length of 20 cm. in the Dutch islands, the 

 largest specimens measured in Thailand have been 14.3 cm. long. 

 Examples 9 to 12 cm. long are common. 



The pigmentation of the fins varies considerably with age and local- 

 ity. The pectoral fins in some specimens (as from Tale Noi) are black 

 almost throughout, and the dorsal, caudal, and anal fins may be black- 

 ish. In some examples the black in the caudal is concentrated into a 

 longitudinal band on each lobe. On the other hand, some specimens 

 show no black whatever on any fins. 



Living colors in specimens taken in the Bangpakong River on June 

 27, 1933, were : Back light green ; sides and below silvery white ; a lus- 

 trous golden band along the side (becoming silvery in alcohol) ; caudal 

 fin yellow-green above and below, with its central part white and its 

 posterior margin black; pectorals blackish. 



The fish is well known to the Siamese under the name pJa paep (flat 

 fish). In the lower Nan River the name fla paep hhao {khao^ white) 

 has been noted. The name pla tong plu recorded by Hora (1923b) as 

 used in Bangkok is properly applied to Cultrops simnensis. 



OXYGASTER POINTONI (Fowler) 



Chela pointoni Fowler, 1934a, p. lOS, fig. 60 (Chiengmai). 



Gulter pointoni Fowler, 1935a, p. 109 (Siam, incidental mention). 



Known from a single specimen, 75 mm. long, taken at Chiengmai, 

 Northern Thailand, presumably from the Ping River, January 5, 1933. 

 It is a rather slender form, with comparatively large scales and with 

 the dorsal fin beginning well in front of the anal. 



The fish is a typical Oxygaster, with nuchal scales extending above 

 middle of eyes. Through error it was later referred to Culter by 

 Fowler. 



Genus MACROCHIRICHTHYS Bleeker 



MacrocMrichthys Bleekek (261), Act. See. Sci. Indo-N6erl. (Cyprinorum), vol. 7, 

 p. 439, 1860. (Type, Macrochirichthys uranoscopus Bleeker.) 



MACROCHIRICHTHYS MACROCHIRUS (Cuvier and Valenciennes) 



Leuciscus macrochirus Cuviee and Valenciennes, 1844, vol. 17, p. 348 (Java). 

 Macrochirichthys uranoscopus Bleekeb, 1863 (301), vol. 3, p. 137 (Menam near 



Bangkok) ; 1865 (356), p. 176 ( Siam ) .— Sauvage, 1881, p. 164 (Siam) ; 1883b, 



p. 153 (Menam Chao Phya). 

 Chela macrochir von Martens, 1876, p. 403 (Bangkok). 

 Macrochirichthys macrochirus Weber and de Beaufort, 1916, vol. 3, p. 54 



(Siam).— Hora, 1923b, p. 149 (Bangkok, Nontaburi ) .—Fowler, 1937, p. 167 



(Mepoon, Kemarat). 



