42 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



and 142.5 cm. wide and the tail 143 cm. long. Another brought to the 

 Chumpom market a short time before weighed 240 kilograms and was 

 said to measure over 4 meters across the disk. 



In allusion to the large black fin in the middle of the tail, the Siamese 

 fishermen call this ray fla kaben tong {tong=^2ig) to distinguish it 

 from other rays in which there is no caudal fin. 



DASYATIS BLEEKERI (Blyth) 



Plate 1 



Trygon lleekeri Blyth. 1860a, p. 41 (Bengal). — Hora, 1924a, p. 464 (Tale Sap). 

 Dasybdtus blcekeri Hora. 1923b, p. 173 (Nontaburi). 



This marine species of India and Burma, described from Bengal in 

 1860, was added to the Thai fauna by Hora in 1923 and 1924 and has 

 since been found as far inland as the mouth of the Menam Nan near 

 Paknampo. With the exception of a specimen from the more or less 

 brackish water of the outer lake of the Tale Sap, collected by Annan- 

 dale in 1916 and reported on by Hora in 1924, all the specimens from 

 Thailand have come from strictly fresh water. Three specimens 

 taken in the lower Menam Nan on October 17, 1930, had the disk 16.8, 

 19.3, and 20 cm. long, and the tail 65, 76, and 78 cm. long. 



In the Bangkok region this fish is known to the fishermen as pla 

 kaben and pla kaben khao, while in the Paknampo district it is called 

 pla kaben nam, chuet (fresh-water ray fish) . 



Subclass TELEOSTOMI 

 Order Isospondyli 

 Family ELOPIDAE: Tarpons, Bigeyes, Bonefishes 



Genus MEGALOPS Lacepede 



Megalops Lacek^de, Histoire naturelle des poissons, vol. 5, p. 289, 1803. (Type, 

 Megalops fllamentosus 'LacepMe=CUipea cyprinoides Broussonet. ) 



MEGALOPS CYPRINOIDES (Broussonet) 



Clupea cyprinoides Beoussonbtt, 1782 (no pagination), pi. 9 (oceans between the 

 Tropics [not Jamaica and Antigua or Rio Janeiro, Brazil] ; Tanna Island, 

 South Pacific). 



Megalops cyprinoides Hoba, 1923b, p. 175 (Nontaburi) ; 1924a, p. 479 (Tale Sap).— 

 Smith, 1930, p. 56 (Siam). 



This fish, the Oriental correspondent of the celebrated tarpon of the 

 western Atlantic {Tarpon atlanticus) , has a very wide distribution in 

 the Pacific and Indian Oceans. 



While primarily marine, it regularly enters fresh water and in Thai- 

 land may be looked for in the lower courses of all large streams. It 

 ascends the Menam Chao Phya for some distance above Nontaburi. 

 In the Chantabun River it is found at least as far upstream as the town 



