428 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



Chao Pliya at Bangkok ; Klong Sok, a tributary of the Tapi River, and 

 the inner hike of the Tale Sap, in the Peninsula. Specimens from 

 Bangkok are in the British Museum as a gift from the Siamese Mu- 

 seum. The species ranges far inland. Two specimens 30 and 32 cm. 

 long were obtained by H. G. Deignan near the headwaters of the Nan 

 River at Muang Ngop, Northern Thailand, April 23, 1936, and one, 

 10 cm. long, from the Meping at Chengmai, Northern Thailand, April 

 22, 1935. 



Day (1878) refers to a "variety" in the Central Provinces and at 

 Hurdwah in which a hump on the anterior part of the back is some- 

 times continued as a ridge as far as the dorsal fin. A specimen, 30 cm. 

 long (which appears to be about the maximum length attained by this 

 species) , from the basin of the Tapi River, possesses the ridge observed 

 in some Indian examples. 



The vernacular name of 'pla katung heo borne by fishes of this type 

 is, in the Bangkok region, expanded for this species into pla hatwng heo 

 Tneuang. 



XENENTODON CANCILOIDES (Blcekcr) 



Belone canciloides Bleieker, 1S53 (85), p. 454 (Pontianak; Panguboeang, Lam- 

 pong Province, Sumatra). 



Xencntodon canciloides Fowlek, 1935a, p. ISO (Bangkok) ; 1937, p. 214 (Bangkok, 

 Kemarat). 



This species had been known only from the fresh waters of Borneo 

 and Sumatra until reported by Fowler from Bangkok and Kemarat 

 (on the Mekong, opposite Cambodia). 



The maximum length seems to be less than 30 cm. 



The fish is extremely like X. cancila. 



Family HEMIRAMPHIDAE : Halfbeaks « 



Of this world-wide family of marine, estuarine, and fresh-water 

 fishes, there are three genera represented in the fresh waters of Thai- 

 land. 



The three genera are characterized as follows : 



la. Dorsal fin with its rays in about equal number to those in anal fin, and its 

 origin over or in advance of that of anal. 

 2a. Dorsal and anal rays in male not modified; species oviparous; maximum 



size about 30 cm Hyporhamphus 



2b. Some anal rays in male enlarged and greatly modified; dorsal fin in some 

 species with some rays elongated ; species viviparous ; maximum size 

 about 20 cm Zenarchopterus 



8 The results of Dr. Albert W. Herre's recent studies of this family (A review of the 

 halfbeaks or Hemiramphldae of the Philippines and adjacent waters, Stanford Univ. Publ., 

 biol. sci., vol. 9, No. 2, pp. 41-86, 1944) could not be incorporated herein, as they appeared 

 while the present publication was in press. — L. P. S. 



