262 SILUEIDJE. 



the cavity of the mouth and the base of the pectoral fins is covered 

 with four longitudinal rows of scutes arranged in three transverst 

 series ; belly with two longitudinal rows of large scutes, six in each 

 row. L. lat. 34 ; the lateral ridges are scarcely visible, and coalesce 

 above the anal fin. Tail much depressed. P. 1/5 ; V. 1/4 ; the 

 outer ray of the pectoral and ventral is slender and but little thickened. 

 D. 1/6. A. 4. Caudal fin but little developed, with the upper and 

 lower rays somewhat prolonged. Uniform olive-brown ; the outer 

 rays of the fins with brown dots. 



Rio Cupai. 

 a-c. From 3 to 5 inches long. Purchased of Mr. Stevens. 



Head partially osseous and rough. Body naked or with bony plates 

 on the back : Sisorina, 



101. SISOR. 

 Sisor, Ham. Bach. Fish. Gang. p. 207. 

 Head depressed, spatulate ; trunk depressed ; tail long and thin. 

 One rather short dorsal fin ; anal short ; ventrals seven-rayed, in- 

 serted below the dorsal. Head partially osseous, rough ; a series of 

 bony plates along the median line of the back ; lateral line rough. 

 Eyes very small. Mouth inferior, small, transverse, with barbels • 

 teeth none. Gill-opening narrow, with moveable opercles. 

 Northern India. 



1. Sisor rhabdophorus. 

 Ham. Bach. Fish. Gang. pp. 208, 379 ; Gray, Ind. Zool. 

 B. 4. D. 7. A. 5. C. 9. P. 1/8. V. 7. 



The upper caudal ray produced into a very long filament. 



Rivers of Northern Bengal. 

 a-b. Presented by Sir A. Smith. 



Description. — Head and trunk rather broad, much depressed ; tail 

 low, tapering, long. Snout long, spatulate, the eye being nearer to 

 the gill-opening than to the end of the snout, The greatest width 

 of the head is between the gill-openings, and two-thirds of its length 

 (to the end of the operculum) ; its length is one-fifth of the total 

 (without caudal), but one-fourth only, if taken to the end of the 

 occipital process. The frontal and parietal portions have longitudinal 

 ridges which converge towards the point of the occipital process ; the 

 interorbital space rather concave ; the remainder of the head is covered 

 with thin skin. The upper profile of the snout is slightly arched ; the 

 intermaxillaries and the cleft of the mouth are entirely on the lower 

 side of the head, and small : the intermaxillaries are small, and form 

 together a crescent-shaped upper lip. The maxillaries terminate in 

 a barbel, which is dilated into a membrane at its base, and extends 

 backwards to the root of the pectoral spine ; the lower lip is pro- 

 duced on each angle of the mouth into a long flap, which is reflected, 

 forming a sort of channel, and terminating posteriorly in barbel-like 

 fringes which extend as far backwards as the maxillary barbels ; a 



