FRESH-WATER FISHES OF SIAM, OR THAILAND 465 



The fish is at home in ponds, lakes, and shiggish waters generally, 

 and has a wide distribution over the Central area. It is naturally ab- 

 sent from Peninsular, Northern, and Western Thailand. The range 

 extends to Cambodia and probably to other provinces of Indo-China. 



A length in excess of 20 cm. is attained. On account of its size and 

 food qualities, the fish is very popular all over the country, and in sec- 

 tions where it does not live there is an extensive trade in a product pre- 

 served by air-drying. 



This fish is well adapted for ponds, and its cultivation in Thailand 

 after the manner of the fresh- water basses in the United States will no 

 doubt be taken up in time. In the Malay States where it was introduced 

 from Thailand it is now widely distributed, abundant, and an im- 

 portant food article. (See Smith, 1933b.) 



In the Supanburi district of Central Thailand, in Klong Kok Kam- 

 yan, there is, or has been, a local race of pla solid which is very much 

 larger than fish elsewhere. It has been reported to be as broad as a 

 man's hand is long, and its local reputation as a food fish has been very 

 high. Owing to active demand and lack of protection, supplemented 

 by possible curtailment of spawning facilities, the fish had become very 

 scarce by 1925 and no examples were obtainable on a special visit made 

 by the writer in that year. 



In the mature male the dorsal fin when flexed reaches to or beyond 

 the base of the caudal fin, while in the female the dorsal fin falls far 

 short of the caudal base, as pointed out in a paper (1930) by Boon 

 Chuay Indrambarya of the Thailand Department of Agriculture and 

 Fisheries. This is a point of practical value in pond-cultural 

 operations. 



An excellent colored plate was published by Chevey (1932b) , but un- 

 fortunately the title reads Trichofodus trichofterus^ and in the text 

 (pp. 65-67) the two species appear to be confused, for the Thai names 

 'pla solid and flo. kodi are attributed to trichopterus. In Thailand the 

 name pla solid is always given to pectoralis and to no other species. 

 The Thai also recognize this fish by the name pla hai mat. 



Family OPHICEPHALIDAE : Serpent-head Fishes 



Genus OPHICEPHALUS Bloch 



Ophicephalus Bloch, Naturgeschichte der auslandischen Fische, vol. 10, p. 117, 

 1797. (Type, Ophicephalus piinctatus Bloch.) 



The serpent-head fishes, representing many species, are a very con- 

 spicuous element of the fish life in almost every part of Thailand, in 

 lowland streams and canals, in upland and mountain streams, and in 

 lakes, ponds, and swamps. The various species exhibit a wide range 

 in size, from about 10 cm. in O. gochuo to over a meter in O. micro- 

 peltes. All the species are eaten by the Thai people, and one of them 



