250 
their spine nearly as long as the dorsal one, its innerborder 
strongly denticulated. Teeth minute, in the jaws in a narrow 
band, on the vomer in two widely separate elliptic patches. 
About 26 slender gillrakers, as long as branchial filaments. 
Yellowish, a blackish band in the lateral line, a less distinct 
but broader band below and above it, the latter more or 
less confluent with a dark median band on the back. A distinct 
black blotch at the origin of the dorsal. Upper surface of 
head, mandibles, caudal, margin of anal and part of the 
remaining fins darkish. In larger specimens the colours are 
fainter. Length about 100 mm. — Named in honour of Mrs. 
Moolenburgh. 
Nomen indig.: Beringgit (Djambi). 
Habitat: Sumatra (Batang Hari river!). 
2. Lais Bleeker. 
(BLEEKER, Ichth. Arch. Ind. Prodr. I Siluri, 1858, p. 170). 
Elongate, compressed, head conical, covered by thin skin, 
through which the bones of the head are partly visible. 
Anterior oval nostrils piercing through the anterior part of 
the snout, posterior nostrils, wide transverse slits, close together 
on the upper surface of the snout. Upper jaw prominent, 
mouth narrow, subterminal. Eyes with a broad circular adipose 
eyelid, situated behind and partly below mouth. Six ribbon- 
shaped barbels. Two maxillary barbels at the corner of the mouth 
and four shorter mandibulary and mental ones, close together 
immediatly behind the symphysis. Short dorsal with a pungent, 
denticulated spine and 7 soft rays. Adipose fin minute. Anal 
elongate, far distant from caudal. Ventrals with 6 rays, far 
behind dorsal. Pectorals with a pungent, denticulated spine. 
Caudal deeply incised. Small teeth in the jaws in a rather 
narrow curved band, those of the vomer in two separate 
straight bands. Gillmembranes free from isthmus and from 
each other. 8—g radii branchiostegi. 
1. Lais hexanema (Blkr.). 
Pangasius hexanema Bleeker, Nat. Tijdschr, Ned. Ind, III. 1852, p. 588. 
Lais hexanema Bleeker, Ichth. Arch. Ind, Prodr. I. 1858, p. 171. — Atl. Ichth. 
II. 1862, p. 72. 
Lais hexanema Ginther, Cat. Brit. Mus, V, 1864, p. 57. 
