162 siltjrid^;. 



beyond the head, the outer ones of the mandible to the base of the 

 pectoral. The teeth on the palate form two widely separate, — ^ 

 elliptic, oblique patches, which are shorter than the eye. 

 The soft dorsal fin is as high as the body ; its spine is very & ^ 

 strong, but a little shorter than the head, and serrated along both 

 edges. Adipose fin longer than the anal. Pectorals scarcely shorter 

 than the head, with a very strong spine, which is as long as that of 

 the dorsal fin. Fins yellowish, blackish in the middle. 

 Sumatra and Borneo. 



a. Type of the species. From Dr. P. v. Bleeker's Collection. 



41. Arius stormii. 



Cephalocassis stormii, Bleek. Prodr. Silur. p. 246. 

 Hemiarius stormii, Bleek. Atl. Ichth. Silur. p. 29. tab. 100. 



D. 1/7. A. 16. P. 1/11. 



The height of the body is contained four times and three-quarters 

 or four times and a half in the total length (without caudal), the 

 length of the head thrice and a half. Head depressed, broader than 

 long, its greatest width being contained once and a fourth in its 

 length. The diameter of the eye is one-ninth of the length of the 

 head, and one-third of the width of the interorbital space. Crown 

 of the head granular ; occipital process triangular, rather longer than 

 broad ; basal bone of the dorsal spine small. Snout depressed, thrice 

 as long as the eye, with the upper jaw 

 projecting beyond the lower. The 

 teeth on the vomer form two small, 

 round, separate patches, contiguous , 



with the palatine bands, which are /^^x ^^^^T^N 

 twice as long as broad. The max- f / x^j 



illary barbel extends to the opercle. 



The soft dorsal fin is higher than the body ; its spine is very strong, 

 scarcely shorter than the head, granulated in front and serrated 

 behind. The adipose fin is neaiiy as long as the dorsal and anal. 

 Pectoral spine very strong, shorter than that of the dorsal fin. Fins 

 yellowish. 



River Mussi (Sumatra). 



a. Type of the species. From Dr. P. v. Bleeker's Collection. 



42. Arius sumatranus. 

 Bagrus sumatranus, Bennett, in Life of Raffles, p. 691. 

 D. 1/7. A. 19. P. 1/9. 

 The length of the head is contained thrice and three-quarters in 

 the total (without caudal) ; its greatest widtb equals its 

 length without snout. Teeth on the palate in two tri- 

 angular patches^ entirely separated along the middle. 

 Six barbels : those of the maxillaries extend to the end V / \ / 

 of the head, the outer of the mandibles to the base of the 



