series larger. Brownish, with a diffuse irregular cephalic, dorso- 

 anal and caudal cross band. Fins brownish. Length 240 mm. 

 [After Bleeker, not seen by us]. 



Habitat: Sumatra (river Enim, river Si Russu, Djapura); 

 ? Borneo (Mahakam river : Leiocassis macropterus Vaillant). 



In rivers. 



4. Leiocassis Bleeker. 



(BLEEKER, Ichth. Arch. Ind. Prodr. I Siluri, 1858, p. 139). 



More or less elongate and robust. Head more or less flattened 

 above, covered by skin or headshields naked. Occipital process 

 touching the basal bone of dorsal spine, or free from it, or 

 both united by a separate shield. Snout more or less promi- 

 nent, above the slightly curved mouth. Eye covered by skin. 

 8 barbels. Dorsal short, its pungent spine with the hindborder 

 smooth or weakly or strongly serrated, the teeth directed down- 

 ward. Adipose fin as long as or longer than dorsal, opposite 

 to anal, which has less than 20 rays. Pectorals with a strong 

 spine, conspicuously denticulated behind. Caudal deeply bifur- 

 cate. Anal with less than 20 rays. Villiform teeth in curved 

 bands in the jaws and on the palate. Gillmembranes nearly 

 totally separated, free from isthmus. Branchiostegals 9 n. 



Synopsis of the species 1 ). 



I. Head covered with smooth skin. 



A. Dorsal spine less than '/ 3 length of head; maxil- 

 lary barbel reaching pectoral. 



1. Depth of body 5 in the length L. fuscus p. 353. 



2. Depth of body 6 in the length L. mahakamensis p. 354. 



B. Dorsal spine at least 2 / 5 length of head. 



1. Maxillary barbel reaching pectoral \ head nearly 



as broad as long L. stenomus p. 355. 



2. Maxillary barbel not extending beyond head, 

 which is longer than broad. 



a. Occipital process reaching basal shield of 



dorsal spine L. poecifapterus p. 356. 



b. Occipital process not reaching basal shield 

 of dorsal spine. 



i) After Tate Regan, Ann. Mag. Nat. Hist. (8) XI. 1913, p. 548. 



