78 silukid^;. 



soft dorsal fin is pointed, as high as, or higher than, the body ; the 

 adipose fin commences immediately behind the dorsal, and is thrice 

 or nearly four times as long. The dorsal spine is slender, more than 

 half as long as the head, slightly tubercular, and serrated at the apex. 

 Pectoral fins rather shorter than the head; their spine is strong, 

 shorter than that of the dorsal fin, and strongly serrated along its 

 inner edge. Ventrals nearly as long as pectorals. 

 Java, Sumatra, and Borneo. 



a. Adult. From Dr. P. v. Bleeker's Collection. 



6. Macrones leucophasis. 

 Bagrus leucophasis, Blyth, Journ. As. Soc. Bene/. 1861, xxix. p. 148. 

 D. 1/7. A. 10. P. 1/9. 



Maxillary barbels reaching to the end of the adipose fin. Eyes 

 separated by an interspace equal to the orbit. Occipital process 

 nearly as in M. gulio. Dorsal spine moderately slender, and pecti- 

 nated behind for its terminal third ; the next two soft rays being 

 longer than the spine. Adipose fin elongated longitudinally. Pins 

 chiefly black ; body dark brown, passing to silky white anterior to 

 the dorsal spine. (Blyth.) 



Burmese rivers. 



Largest specimen 5£ inches long, 11 inch high at the dorsal spine, 

 and length of dorsal spine 1-^ inch. 



II. Adipose fin not much longer, or shorter than anal. 



A. A separate interneural shield on the nape. 



7. Macrones aor. 



Pimelodus aor, Ham. Buck. Fish. Gang. pp. 205, 379. pi. 20. fig. 68. 

 Bagrus aor, Cuv. 8f Veil. xiv. p. 405 ; Jacquem. Voy. Ind. Poiss. pi. 16. 



fig. 1; Bleek. Verh. Bat. den. xxv., Hindost. p. 116. 

 Platystoma seenghala, (fykes, Trans. Zool. Soc. ii. p. 371. tab. 65. fig. 2. 

 Bagrus aorellus, Blyth, Jemrn. As. Soc. Beny. xxvii. p. 283. 



B. 12. D. 1/7. A. 13. P. 1/10. V. 6. 



Head and body rather elongate ; the greatest width of the head is 

 contained once and two-thirds in its length. Snout spatulate, its 

 length being two-fifths of that of the head ; the upper jaw is the 

 longer ; interneural shield twice or thrice as long as broad in adult 

 specimens, narrower in young ones. The maxillary barbels are very 

 long, extending to or beyond the adipose fin. Dorsal spine very 

 strong, serrated behind, as long as, or even longer than, the head in 

 full-grown specimens, rather shorter in young ones. The adipose fin 

 commences at some distance behind the dorsal, and is not twice as 

 long as the latter, and nearly as high as the hinder part of the tail. 

 Caudal fin deephy forked, with the upper lobe produced. Pectoral 

 spine as strong as that of the dorsal fin, with a finely serrated outer 

 edge, and with a coarse scrrature along its inner margin ; its length 



