199 
of head; it is situated at the boundary between the first and 
second 1/, 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 1'/, 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 S. 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. 
Di) Be AG Po Ta Gly. Vig 
Height nearly 5 times in total length (without caudal). 
Head 6'j, times. Upper jaw nearly inconspicuously prominent. 
Cleft of mouth reaches vertically below middle of eye. Eye 
'/, 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 '/, 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 1'/, 
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, 
