362 BULLETIN 1S8, UNITED STATES NATIONAL MUSEUM 



marked with a broad, straight dark median band from the head to 

 the base of the caudal fin, a decurved dark band from the head to a 

 point over the posterior part of anal fin (this band broad anteriorly 

 and tapering to a point posteriorly), the bands separated from the 

 blackish back and from each other by whitish interspaces ; dorsal fin 

 gray-black, with a whitish posterior edge; caudal dark gray or gray- 

 black, with upper, lower, and posterior margins whitish ; anal white, 

 with a median black band; and paired fins m.ostly gray -black. The 

 maxillary barbel reaches to or nearly to the base of the pectoral fin, 

 and the mandibulary barbel to the center of or beyond the eye. The 

 anal rays are iv, 30 to iv, 32. The description makes no reference to 

 palatine teeth, but the published figure suggests that the palatine 

 teeth may be represented in the widened posterior ends of the well- 

 separated vomerine patches. 



This species appears to be close to P. pleurotaenius but is of a 

 different coloration, especially in the possession of a second longi- 

 tudinal blackish band. 



PANGASIUS NASUTUS (Bleeker) 



Pseudopangasius nasuUis Bleeker 1863 (324), p. 72 (Borneo). 



There were no Thailand records for this Bornean and Sumatran 

 species until the writer found it in the upper Menam Chao Phya. It 

 is confined to that river and collateral streams, and is rather uncom- 

 mon. Localities from which specimens have been preserved are 

 Paknam, Koh Yai. Angtong, Paknampo, and the Bangham River at 

 Lopburi. 



A length of 50 cm. is reported from the Koh Yai section, and one 

 specimen over 41 cm. long was collected there. The usual run of the 

 fish taken for market is 25 to 35 cm. long. The smallest examined, 

 taken at the head of the Menam Chao Phya in the vicinity of Pak- 

 nampo in November, was 17.5 cm. long. The maximum length reported 

 by Bleeker for the Dutch islands was 90 cm. 



The species may be recognized easily by the comparatively long 

 prominent snout and the position of the eyes, which are entirely above 

 the level of the angle of the mouth. 



In life, the general color is light gray, with the belly pure white, the 

 top of the head ash green, and the underside of the head golden. 



The vernacular name given to this fish is pla saiyu (hinge fish) , some- 

 times modified to pla scdyu pueh (albino hinge fish) . 



PANGASIUS BEANI H. M. Smith 

 Pangasius ieani Smith, 1931a, p. 26 (Lopburi River). 



Only a single specimen of this species has been obtained ; it is 20 cm. 

 long and came from a klong off the Lopburi River near Ayuthia. The 



