354 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



fresh water in the extensive collecting done for the Siamese Bureau of 

 Fisheries, and its admission to this catalog is based on Fowler's record 

 of eight specimens from Paknam, near the mouth of the Menam Chao 

 Phya. Paknam is the headquarters of a large number of fishermen 

 operating traps and other apparatus in the Gulf of Siam, their catch 

 being sent to Bangkok by water or rail. Many fish of this species are 

 often caught in the traps, but all are small and their food and market 

 value is low. 



This fish reaches a length of 25 to 30 cm., and it is respected by 

 fishermen because of the very painful, sometimes dangerous, wounds 

 inflicted with its serrated dorsal and pectoral spines. 



Among the Thai it is called called fla duk tale^ pla sam heo^ and 

 'pla pet keo. 



PLOTOSUS CANIUS Hamilton 



Plotosus cankis Hamilton, 1822, pp. 142, 374 (Bengal).— Bleekee, 1865 (347), 

 p. 34 (Siam) ; 1S65 (356), p. 175 (Siam).— Hora, 1924a, p. 467 (Tale Sap).— 

 Smith, 1930, p. 54 ( Siam ) .— Fowlek, 1935a, p. 96 (Bangkok, Sriraclia). 



Plotosus caninus Hora, 1923b, p. 166 (Menam Chao Phya at Noutaburi). 



The range of this fish is from India, Burma, and Ceylon to Thailand, 

 Malaya, and Indo-Australian Archipelago, in the sea, in estuaries, and 

 in the lower courses of rivers. The species abounds on the coasts of 

 Thailand and goes up some of the rivers into water that is quite f resli. 

 In the Menam Chao Phya it is regularly found as far as Nontaburi, 

 some miles above Bangkok, but is most common in the Paknam section ; 

 a length of 75 cm. is reached in this river. In the Chantabun River 

 it is at times numerous, as in June 1926, when over a hundred were 

 observed in the local market in one day, the largest 58 cm. long. 



The vernacular name for this fish in Thai is pla dtik tale. 



Family SCHILBEIDAE 



The schilbeid catfishes of Thailand constitute a striking and well- 

 marked group. Some of them are among the largest fresh-water 

 fishes of Asia. The family name is derived from jSchilhe, the oldest 

 genus (Oken, 1817). Weber and de Beaufort and others have given 

 the family as the Pangasiidae, from Pangasius (Cuvier and Valen- 

 ciennes, 1840). Jordan (1923) separated the Pangasiidae from the 

 Schilbeidae, with the Clariidae interposed, placing therein Pangasius 

 and the nominal genera Pseudopangaslus Bleeker (1862) and Neo'pan- 

 gasius Popta (1904). In all important structural characters Heli- 

 cophagus, Laides^ and Pangasianodon are too close to Pangasius to 

 warrant separation therefrom in a distinct family. 



The seven local genera may be distinguished without much difficulty. 

 A convenient differential feature is the number of pairs of barbels, 

 taken in conjunction with the vomero-palatine teeth. Other dis- 

 tinguishing characters are as follows : 



