Eye 5 7, situated in the second */ 4 of the length of the 

 head. Height of dorsal slightly less than head, its strong 

 flattened spine slightly shorter, its hindborder denticulated. 

 Adipose fin shorter than snout, situated above the beginning 

 of the last '/ 3 of the anal, its height less than snout. Anal more 

 than thrice in length. The outer longer rays of the anal nearly 

 equal to postorbital part of head. Pectorals about as long as 

 head without snout, their strong flattened spine somewhat 

 shorter, their inner border denticulated. Three groups of 3 4 

 rather wide mucous pores in the axil of the pectorals. Cylin- 

 drical teeth with brown tips forming a broad curved band in 

 the jaws, those of the vomer in two distant narrow curved 

 bands. Pearlcolored, upper surface dark. Fins reddish, dorsal 

 and margin of caudal dark. A whitish spot on the top of the 

 head. Length over 460 mm. 



N o m e n i n d i g. : Paten (Palembang). 



Habitat: Sumatra (Palembang !). 



In rivers. 



2. Helicophagus waandersi Blkr. [Fig. 102 p. 252]. 



Helicophagus Waandersii Bleeker, Ichth. Arch. Ind. Prodr. I Siluri 1858, p. 175. 



Atl. Ichth. II. 1862, p. 77. 

 Helicophagus Waandersi Giinther, Cat. Brit. Mus. V. 1864, p. 65. 



B. 9; D. n. 67; A. 37 38; P. i. 10 ii; V. 6. 



Elongate, compressed, head conical, profile behind dorsal 

 nearly straight, sloping down before dorsal in a straight line 

 to the conical snout. Height 4 ! / 2 5, head a little more or 

 less than 5. Mouth subterminal, snout soft, prominent, behind 

 its frontborder pierced through by the wide anterior nostrils 

 which look upwards and are surrounded by a prominent rim; 

 posterior nostrils more distant from each other, situated midway 

 between anterior nostrils and eye, with a valve at the front- 

 margin. Above the corner of the mouth a maxillary barbel 

 extending on the pectoral; mandibulary barbels, originating 

 close together at some distance behind the symphysis, some- 

 what shorter. Eyes more than 4, situated at the end of the 

 first half of the head, somewhat shorter than snout. Height 

 of dorsal about equal to head without snout, its spine some- 

 what shorter, very strong, flattened, the hindborder strongly 

 denticulated ; adipose fin above the last '/a f tne ana l> its 

 height nearly equal to snout; anal 2 3 / 4 in length. Ventrals 



