50 



culum to middle of base of caudal, where it ends in a dark 

 patch. Fins hyaline. A dark median band along the back. 

 Length of single specimen known 42 mm. [Type of the species 

 in the Zoological Museum of Amsterdam]. 



Habitat: Sumatra (Gunung Sahilan on river Kampar!). 



3. Chela Hamilton Buchanan. 



(HAMILTON BUCHANAN, Fishes of the Ganges 1822, p. 258. Swainson, Nat. 

 Hist, of Fishes, Amphib. and Reptiles II. 1839, p. 285). 



Oblong or elongate, much compressed. A regularly convex 

 trenchant edge from throat to anus. Dorsal profile more or 

 less straight. Head pointed. Mouth directed upward. Chin pro- 

 minent. Mandibular symphysis with a prominent hook, fitting 

 into an emargination of the symphysis of the upper jaw. No 

 barbels. Eye large, with a free orbital margin. Dorsal short, 

 without strong spines; totally or with its greater part opposite 

 to anal, which is long and many-rayed. Caudal forked. Ventrals 



Fig. 22. Chela oxy gas tr aides (Blkr.). 



inserted somewhat above the abdominal profile, with at least 

 6 branched rays. Pectorals elongate, situated above the ventral 

 profile. Scales thin, of moderate or small size. Dorsal and 

 nuchal scales smaller than the others, the nuchal ones beginning 

 t above the eye. Lateral line without abrupt bend above the 

 pectorals, but gently curved downwards and running in the 

 lower half of the tail. Pseudobranchiae present. Branchial opening 

 reaching below hindmargin of praeoperculum. Gillmembranes 

 broadly united to isthmus. Gillrakers short, cylindrical, widely- 

 set. Pharyngeal teeth slender, hooked, without serrature, in a 

 triple series. 



