SILUBIDjE. 105 



Barbels six or eight, the two mandibular 

 pairs arising on a transverse line. Dorsal 

 with one spine and six rays ; an adipose 

 fin ; a pectoral spine. Anal rather short. 

 Ventral with six rays. Air-bladder en- 

 closed in bone 31. GAGATA. 



Gill-niembranes not confluent with the skin 

 of the isthmus, or only slightly adherent. 

 No palatine teeth. Barbels eight, the 

 two mandibular pairs not arising on a 

 transverse line. Dorsal fin with one spine 

 and six to eight rays; an adipose fin. 

 Anal rather short. Ventral with six rays. 

 Air-bladder enclosed in bone 32. NANGHA. 



First group. HYPOSTOMATINA. 

 1. Genus SISOR, Hamilton Buchanan. 



Branchiostegals four. Gill-openings narrow and mostly lateral, 

 the gill-membranes confluent with the skin of the isthmus. Head 

 and anterior portion of the trunk broad and depressed. Eyes 

 small. Mouth small, transverse, the upper jaw the longer. 

 Nostrils round and approximating, but separated by a valve. One 

 maxillary pair of barbels with broad bases, and about five mandi- 

 bular pairs. Teeth absent. A short dorsal fin destitute of a 

 distinct spine ; pectoral with, a strong spine. Ventral having 

 seven rays, and situated below the last portion of the dorsal fin. 

 Upper portion of body covered with bony plates. Anal with six 

 rays. Caudal with its upper ray very prolonged. Air-bladder 

 enclosed in a bony capsule. An axillary pore. 



Geographical Distribution. Indus and upper portions of the 

 Jumna and Ganges rivers. 



112. (1.) Sisor rhabdophorus. (Fig. 43.) 



Sisor rhabdophorus, Ham. Buck. Fish. Ganges, pp. 208, 379 ; Day, 

 Fish. India, p. 491, pi. cxv, figs. 1, la, \b (see synon.). 



Chennuah, Hind. ; Kir^ri-dee, Sind. 



B. iv. D. 1/6. P. 1/8. V. 7. A. 6 (2/4). C. 11. 



Length of head 5|, of caudal 11, height of body contained 11 

 times in the total length, excluding the caudal filament, which in 

 some specimens equals the length of the body. Eyes small, 

 nearer the gill-opening than the end of the snout, which is rather 

 pointed. A median longitudinal groove on the head reaches to the 

 base of the occipital process. The greatest width of the head 

 equals two thirds of its length. Numerous rough ridges exist on 

 the head, which is covered by very thin skin. The basal bone of 

 the dorsal fin has an anterior and two lateral processes covered 



