19. AILIA. 55 



and extend to the eye ; pectoral about as long as the head, with the 

 spine slender and slightly denticulated. 

 Sumatra. 



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



2. Hemisilurus scleronema. 

 Bleeker, Atl. Ichth. Silur. p. 93. tab. 101. 



B. 10. A. 103. P. 1/15-16. V. 8. 



The height of the body is contained five times and a half in the 

 total length (without caudal), the length of the head seven times 

 and a quarter. Barbels cartilaginous, rigid, much shorter than the 

 eye. Pectoral about as long as the head, Avith the spine slender and 

 slightly denticulated. 



Java. 



The single specimen known is in the Leyden Museum. 



18. SILURANODON. 



Silurus, sp., Cuv. <S* Vol. 



Siluranodon, Sleek. Proclr. Silur. p. 255. 



One short dorsal fin without pungent spine ; no adipose fin ; the 

 anal fin terminates close by the caudal, which is forked. Barbels 

 eight : one at the nostrils, one to each maxillary, and four behind 

 the chin, the roots of the latter being nearly in the same transverse 

 series. No teeth in the jaws or on the palate. Eyes behind and 

 below the angle of the mouth. Neck not elevated. Ventral composed 

 of six rays. 



Nile. 



1. Siluranodon auritus. 



Oued denne (of the Arabs). 



Silurus auritus, Geoffr. Descr. Eg. Poiss. pi. 11. figs. 1 & 2 ; Cuv. $• Veil. 

 xiv. p. 368. 



B. 9. D. 5. A. 80. P. 1/9. V. 6. Vert. j£J. 



The nasal and maxillary barbels are shorter than those on the chin, 

 which are one-third or one-fourth longer than the head. Pectoral 

 spine rather strong, serrated, and nearly as long as the first ray. 

 Silvery. 



Nile. 



19. AILIA. 

 Ailia, (Gray) Cuv. 6/ Val. xv. p. 538. 



Adipose fin exceedingly small ; no other dorsal fin *. The anal 

 fin terminates at a short distance from the caudal, which is deeply 

 forked. Barbels eight : one between the nostrils, one to each max- 

 illary, and four immediately behind the chin, the roots of the latter 



* There is a small hole in the skin where the dorsal fin ought to have been 

 placed ; it is at a short distance from the occiput, and a little before the vertical 

 from the ventral fins. 



