199 



of head; it is situated at the boundary between the first and 

 second 1 / 3 of the head, shortest distance between eyes equal 

 to half length of head. Maxillary barbel reaches nearly to 

 the half of the length without caudal. Mandibulary barbel 

 shorter, not reaching to end of pectorals but somewhat below 

 the insertion of the ventrals. Length of pectorals equal to 

 that of head. Pectoral spine half as long as the fin, posteriorly 

 finely denticulated. Ventrals exactly vertically below dorsal, 

 equal to the distance between hindmargin of eye and hind- 

 margin of the branchial opening. Distance between tip of 

 snout and origin of anal equal to i'/ 2 times height of body. 

 Anal confluent with caudal. Caudal obliquely truncated, its 

 superior longest rays slightly longer than the greatest height 

 of body. Total length without caudal 16 cm. [After Volz]. 



Locality: Sumatra: Upperlangkat (Danau near Sukaranda). 



The only differences from 5. phaiosoma seem to be : A. 64 

 instead of A. 53 58 and that the gape of mouth only reaches 

 below frontborder of eye and not to its middle. 



3. Silurichthys indragiriensis Volz. 



Silurichthys indragiriensis Volz, Revue Suisse Zool. XII. 1904, p. 464. 



D. 4; A. 49; P. i. 9; V. 7. 



Height nearly 5 times in total length (without caudal). 

 Head 6 1 / 2 times. Upper jaw nearly inconspicuously prominent. 

 Cleft of mouth reaches vertically below middle of eye. Eye 

 ! / B of length of head. Maxillary barbel reaching to middle of 

 body without caudal; mandibulary barbel nearly to end 

 of pectoral fin. Length of pectoral equal to head, its spine 

 slightly less than J / 3 of length of head and equal to snout. 

 Dorsal slightly before ventrals. Ventrals about half as long as 

 pectorals. Distance from tip of snout to anal equal to i ! / 2 

 times height of body. Anal and caudal connected. Height of 

 dorsal equal to distance from hindmargin of eye to tip of 

 snout. Dorsal profile straight, slightly sloping towards head 

 and tail. Dark brown above, with irregular larger blackish 

 spots, sides fainter, irregularly marmorated and speckled with 

 dark. Dorsal light, with dark markings. Pectorals and ventrals 

 light, .the first with numerous black irregular spots, the latter 

 with dark markings towards the base. Anal with light border, 



