56 SILURID^. 



being nearly in the same transverse series. Teeth in the jaws villi- 

 foi'm ; teeth on the vomer minute, in two separate small patches. 

 The nostrils of one side are close together, open, the anterior being 

 quite in front of the snout. Head covered with thin skin. Upper 

 jaw rather longer than the lower. Orbit with a broad circidar eye- 

 lid, behind the angle of the mouth. Ventral composed of six rays. 

 Bengal. 



1, Ailia bengalensis. 



Malapterurus coila, Ham. Buch. Fish. Gany. pp. 158, 375. 



Silurus (Acanthouotus) cuvieri, Gray, Illustr. Ind. Zool. (very bad ; 



from a deteriorated specimen). 

 Malapterus (Ailia) benoalensis. Gray, Illustr. Ind. Zool. 

 Ailia bengalensis, Cuv. §• Val. xv. p. 538 ; Bleek. Verh. Batav. Genootsch. 



XXV., Beng. i^ Hind. p. 



A. 70-72. P. 14. 



All the barbels are subequal in length, extending to about the 

 middle of the length of the fish. The pectoral spine is slender, nearly 

 as long as the head, the length of which is one-sixth of the total 

 (without caudal). The height of the body is one-fifth of the total. 



a-h. Tj-pes of the species. Ganges. Presented by G. R. Water- 

 house, Esq. 



e-d. Half-grown. Calcutta. From the Collection of Messrs. v. 

 Schlagintweit. 



2. Ailia af&nis. 

 A. 60-61. P. 13. 



Nasal and maxiUary barbels subequal in length, extending to, or 

 nearly to, the middle of the length of the fish ; mandibulaiy barbels 

 rather shorter. The pectoral spine is very slender, as long as the 

 head, the length of which is one-sixth of the total (without caudal). 

 The height of the body is more than one-fifth of the total length 

 (without caudal). Otherwise very similar to A. bengalensis. 



Himalayas, Assam. 

 a~h. Four inches long. Kulu. From the Collection of Messrs. v. 



Schlagintweit. 

 c. Three and a quarter inches long. Assam. From the Collection 

 of the East India Company. 



20. SCHILBICHTHYS. 



Schilbe, sp., Cuv. ^ Val. 



Schilbeichthys, Bleek. Prodr. Silur. p. 255. 



One short dorsal fin with a pungent spine ; no adipose fin ; the 

 anal fin terminates at some distance from the caudal, which is forked. 

 Barbels eight, as in Ailia. Vomerine and palatine teeth present. 

 Nostrils close together, at the end of the snout, very wide, the pos- 

 terior twice as wide as the anterior. Head covered with skin. The 



