FRESH-WATER FISHES OF SIAM, OR THAILAND 49 



as constituting undoubted fresh-water records and are believed to be 

 based on market specimens from the Gulf of Siam. 



la. Abdominal scutes 25 or 26, of which 7 are posterior to base of ventrals ; anal 

 origin under posterior half of base of dorsal ; origin of dorsal fin somewhat 

 nearer to tip of snout than to base of caudal kampeni 



16. Abdominal scutes 28 to 31, of which 9 to 11 are posterior to base of ventrals; 

 anal origin under hindermost rays of dorsal; origin of dorsal fin midway 

 between tip of snout and base of caudal dussumieri 



ILISHA KAMPENI (Weber and de Beaufort) 



Pellona kampeni Webee and de Beaufort, 1913, vol. 2, p. 87 (Batavia, Java ; Balik- 

 papan, Borneo). 



Otherwise known only from Borneo and Java, this species is entitled 

 to a place in this catalog from having been taken at two fresh-water 

 localities in Peninsular Thailand, the Tapi River near Bandon in 

 September 1923, and the inner lake of the Tale Sap at Pak Bhayoon in 

 October 1923. The specimens agree closely with the original descrip- 

 tion of Weber and de Beaufort. 



Tlie largest is 17 cm. long. 



ILISHA DUSSUMIERI (Cuvier and Valenciennes) 



Pellona dussumieri Cuviek and Valenciennes, 1847, vol. 20, p. 316 (Malabar; 

 Coromandel; Bombay). 



This is a common species of the East Indies and Thailand, primarily 

 marine but haunting the mouths of rivers and sometimes ascending 

 streams, probably for spawning purposes. On June 10, 1926, fishes 

 approaching the spawning condition entered the estuary of the Chan- 

 tabun River and were caught in set nets, and the next day many were 

 taken in the lower river and sold in Chantabun, over 200 being observed 

 in the market. 



The largest examples were 46 emi long, many 28 to 37 cm. 



In the Chantabun district, where this fish is well known to fishermen 

 and marketmen, it is called pla lek. Elsewhere around the shores of 

 the Gulf of Siam the vernacular name is yla taluerk^ shared with vari- 

 ous other species. 



Genus OPISTHOPTERUS Gill 



Opisthopterus Gill, Proc. Acad. Nat. Sci. Philadelphia, 1861, p. 38. (Type, 

 Pristigaster tartoor Cuvier and Valenciennes.) 



OPISTHOPTERUS MACROGNATHUS Sleeker 



Opisthopterus macrognathus Bleeker, 1866 (381), p. 299 (Sumatra and Borneo). 



Although long known from Singapore, Simiatra, Borneo, and Java, 

 in sea and estuaries, this well-marked species has rarely been recorded 

 in localities outside the Indo- Australian Archipelago. It is, however, 



