232 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



Squamation: Scales in lateral line 36, in transverse line from 

 middle of back to middle of ventral surface 7.5-1-5.5, between lateral 

 line and base of ventral fin 4, in predorsal region 14, circumpeduncular 

 16 ; base of dorsal and anal fins scaly ; lateral line gently decurved, de- 

 scending to about seventeenth scale of lateral line, thence running 

 nearly straight to midbase of caudal. 



Fins : Dorsal fin arising over base of ventrals, midway between tip 

 of snout and base of caudal fin ; dorsal rays iv, 8 ; last simple ray about 

 as long as head, ossified, and bearing 17 or 18 prominent denticuhi- 

 tions and about 5 minute ones ; free margin of dorsal concave ; caudal 

 deeply forked, longer than head ; anal rays iii, 5, last simple ray 0.75 

 head; ventrals and pectorals subequal, ventrals reaching to anal 

 and pectorals reaching nearly to ventrals. 



Coloration : Body and head uniform silvery white ; dorsal mem- 

 branes with scattered minute black spots; caudal membranes dusky, 

 becoming more intense along inner sides of the lobes; other fins 

 hyaline. 



Type and paratype. — The type (U.S.N.M. No. 119495), 6.9 cm. long, 

 was taken July 21, 1923, from a short tributary of the Menam Chao 

 Phya near the ancient capital city of Ayuthia. A paratype (U.S.N.M. 

 No. 119496) , with the same data, is 6.6 cm. long. 



Remarks. — This species, easily recognized by a combination of 

 characters (thick lips completely covered with low papillae, narrow 

 annular eyelid, absence of rostral pores or tubercles, dorsal fin with 8 

 branched rays and a strongly ossified and denticulated last simple 

 ray, etc.), was not met with elsewhere or on any other occasion. 



Genus BARBICHTHYS Bleeker 



BarUchthys Buseker (261), Nat. Tijdschr. Nederl.-Indie, vol. 20, p. 424, 1859-60: 

 (Type, BarMcMhys laevis Bleeker.) 



BARBICHTHYS LAEVIS (Cuvier and Valenciennes) 



Barhus laevis Cuvier and Valenciennes, 1842, vol. 16, p. 192 (Java). 

 BarUchthys laevis Weber and de BEAtrFORT, 1916, vol. 3, p. 208, figs. 77-79 

 (Siam).— Fowler, 1935b, p. 513 (Old Chiengsen). 



Tlie range of this species embraces Java, Borneo, Sumatra, the 

 Malay Peninsula, Indo-China, and Thailand. The fish is generally 

 distributed in Central Thailand from Bangkok to the Paknampo dis- 

 trict; it is known also from the Mekok at Oiiengmai, from the Mekong 

 at Old Chiengsen, from the Province of Patani in the Peninusula, 

 and from "Western Siam" (a specimen in the British Museum being 

 so labeled). 



A length of 34 cm. is attained by the fish in the East Indies but 

 examples over 25 cm. long are not often met with in Thailand. 



