1905.] NATURAL SCIENCE« OF PHILADELPHIA. 491 



from Sumatra,^ taken at Batu Sangkar in Padangsche Bovenland, and 

 collected by Harrison and Hiller. The smallest of these differs in the 

 color markings which are very pronounced. The vertical fins also 

 have blackish bases with distinct margins and their edges with whitish 

 blotches. The spots on the sides are distinct and the lower surface of 

 the body is decidedly paler. The largest Sumatran example also shows 

 the following: Head (without rostral appendage) 5^^; depth 8|-; D. 

 XXXVI, 80?; A. II, 72?; P. 22; scales about 285 in a lateral series to 

 base of caudal ; width of head 3f in its length ; depth of head 2f ; snout 

 3^; eye 8; mouth 4f; pectoral 2f; caudal 3^; interorbital space 1^ 

 in eye; eye 2| in snout. My figure also shows the caudal confluent 

 almost entirely with the rayed dorsal and anal. This is in entire 

 agreement with my largest Sumatran example which it was supposed 

 to represent. However, the others, especially the smaller ones, have 

 it distinct and with the ends of the caudal rays free. They also show 

 the margins of these fins whitish. Surely Day's figure and account 

 of Mastacemhelus urdcolor^ represents a distinct species. 



Fig. 8. — Mastacemhelus vaillanti Fowler. 



47. Mastacemhelus vaillanti sp. nov. 



Head (without rostral appendage) 7; depth 9; D. XXVIII. 58?; A. 

 Ill, 65?; caudal 14?; P. 22; scales aboirt 164 in a lateral series below 

 lateral line to caudal; width of head 4 in its length (without rostral 

 appendage); depth of head 2f ; snout 3^; eye 8; mouth 5J; maxillary 

 4; pectoral 3; caudal about 2; interorbital space about If in eye; eye 

 2 in snout. 



Body long, strongly compressed, deep, especially posterior half or 

 tail, and anterior half tapering more narrowly forward to tip of snout. 

 Greatest depth at vent. Caudal peduncle not evident, its width would 

 be about 6^ in head without rostral appendage. 



Head small, long, well attenuated and greatly compressed. Profiles 



*Uourn. Acad. Nat. Sci. Phila., XII (2), 1904, p. 501, PI. 8, upper figure. 

 "^Fishes of India, II, 1876, p. 3.39, PI. 72, fig. 3. 

 32 



