478 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



The maximum length is about 25 cm. Full maturity is reached at 

 17 or 18 cm. 



In the fine-meshed set nets (pongpang) operated in the Menam 

 Chao Phya and other rivers, and in the fine-meshed seines hauled at 

 the head of the Gulf of Siam, incredible quantities of adult and young 

 of this species are caught during the rains. At times, between June 

 and September, literally millions may be taken daily, the larger fish 

 being sent to market and the young, from 2 cm. upward, being used as 

 duck feed and fertilizer. Both old and young are of a golden yellow 

 color, with the back gray or green. 



The seven detached pectoral filaments are of very unequal length; 

 the three upper may be twice the length of the fish. 



In allusion to the sparse chin whiskers worn by the Braliman priests 

 in Thailand, this fish is called pla nuad pram (Brahman beardfish). 



Family CENTROPOMIDAE 



The arrangement proposed by Regan and by Weber and de Beaufort, 

 by which the genera Lates and Amba^sis {Chanda) are placed in this 

 family, is here followed. Jordan (1923) assigned these genera to 

 separate families (Latidae and Ambassidae). The differential char- 

 acters of the two genera here allocated are as follows : 



la. Scales ctenoid ; parietal and occipital bones with a crest ; a supplementary 

 maxillary bone; maxillary reaching beyond ej^e; preoperculum with a 

 single edge; caudal fin rounded; size large lates 



lb. Scales cycloid ; only occipital bone with a crest ; no supplementary maxillary 

 bone ; maxillary not extending beyond eye ; preoperculum with a double 

 edge; caudal fin forked; size small or medium Chanda 



Genus LATES Cuvier and Valenciennes 



Lates CuviEE and Valenciennes, Histoire naturelle des poissons, vol. 2, p. 88, 

 1828. (Type, Lates nilotica (Cuvier and Valenciennes) =Perca nilotica 

 Linnaeus.) 



LATES CALCARIFER (Bloch) 



Holocentrus calcarifer Bloch, 1790, vol. 4, p. 100 (Japan). 



Lates calcarifer Bleekeb, 1865 (356), p. 173 ( Siam ) .— Hoba, 1923b, p. 176 

 (Nontaburi).— ViPULYA, 1923, p. 223 (Bangkok).— Smith, 1930, p. 56 (Siam). 



From the Persian Gulf to Australia and China, this is a well-known 

 and important fish in marine, brackish, and fresh waters. It occurs 

 on all the coasts of Thailand, and it is especially common about the 

 head of the Gulf of Siam and in the streams debouching therein. In 

 the Menam Chao Phya this fish is regularly found as far upstream as 

 Nontaburi or some distance farther. It is most common in the river 



