6 4 



caudal. Head 3.7 4.1 in length, 4.8 5.1 in length with caudal. 

 Eye 3.3 4, equal to or slightly shorter than snout, and equal to 

 or slightly shorter than flat interorbital space. Cleft of mouth 

 obliquely ascending, its anterior end in the level of the superior 

 border of the eye, its posterior end about one third eye diameter 

 distant from eye. Notch on the border of the upper lip very 

 deep, receiving the strongly developed symphysial knob. Origin 

 of dorsal before or slightly before the middle between snout 

 and last caudal scales, opposite to the nth lateral scale, 

 separated from head by 1 1 scales. Dorsal truncate, its height 

 slightly less than that of body, much nearer to ventrals than 

 to anal. Anal concave, its height about one third less than that 

 of the body. Ventrals not reaching anal, one eye-diameter 

 nearer to anal than to operculum, opposite to io th lateral scale. 

 Pectorals equal to distance from nostril to hindborder of oper- 

 culum, the distance between their tip and the origin of ventrals 

 equal to eye. Caudal about equal to head, deeply incised, its 

 longest outer rays much more than twice the length of the 

 middle ones. Least height of caudal peduncle more than twice 

 in its length and equal to postorbital part of head. Seven rows 

 of scales between the lateral lines, counted over the back of 

 the middle of the caudal peduncle. Eightteen rather long gill- 

 rakers on the first branchial arch, about equal to one third eye- 

 diameter in length. Colour of formol specimens greyish brown 

 in upper half, yellowish white in lower half, separated by a 

 faint dark lateral band on the body; in its posterior half a 

 black line ending in a black spot at base of caudal, a median 

 dorsal black line. Fins, especially the caudal, with a dark hue. 

 Length 120 mm. [Type of the species in the zoological Museum 

 of Amsterdam]. 



Habitat. Sumatra (Atchin : Lake Tawar!), collected by Mr. 

 V. D. WERFF. We received this new species through the kind 

 intervention of Lieutenant Colonel Dr. A. J. SALM from Mr. 

 V. D. WERFF, who got them from Laut Tawar, a large lake 

 situated in the interior of Atchin (Gajo-territory). He had the 

 kindness to inform us that the natives assured him that this 

 fish is not known from any other waters. His collection con- 

 tains 6 specimens of 98 120 mm. which are called by the 

 natives Ikan 1'as. He informs us that they are only caught 

 during the north eastern trade-winds, which is the wet season. 

 In the collection are 4 specimens of about 85 mm. which are 



