222 SILTJRID.E. 



Synopsis of the Species. 



I. Ventral fins midway between end of snout and root of caudal, or a little nearer 

 (less than ^) the former ; nasal barbel shorter than head *. 

 A. Maxillary barbel not or but little longer than head, except in the very 

 young ; at least 20 gill-rakers on anterior arch. 

 1. Length of head 3 to 3f times in total length f ; vomerine teeth forming 

 an uninterrupted or scarcely interrupted band or patch ; distance 

 between occipital process and dorsal fin at least 3| times in length of 

 head. 

 a. Head granulate above (under the skin), except in the very young ; 

 D. 62-82, A. 46-65. 

 a. Vomerine teeth mostly pointed or granular-subconical, forming a 

 band which is not broader than the band of prsemaxillary teeth ; 

 distance between occipital process and dorsal fin 3^ to 7 times in 

 length of head. 

 20-27 gill-rakers on anterior arch ; distance 

 between dorsal and caudal 1-2| diameters 



of eye 1. C. cmguillaris, L., p. 226. 



25 (in very young)-80 gill-rakers on anterior 

 arch ; distance between dorsal and caudal 

 1^-2 diameters of eye ....... 2. C. gariepinus, Burch., p. 228. 



87 gill-rakers on anterior arch ; distance be- 

 tween dorsal and caudal 3 diameters of eye. 3. C. moorii, Blgr., p. 230. 



/8. Vomerine teeth all or mostly granular, forming a crescentic band 

 with or without posterior process. 

 30-40 gill-rakers on anterior arch ; band of 



vomerine teeth as broad as or a little 



narrower than band of prsemaxillary teeth : 



head not more than If times as long as 



broad, 4-7 times its distance from dorsal. 4. C. senegalenm, O. & V., p. 23.1. 

 25 (in Very young)-100 gill-rakers on anterior 



arch ; band of vomerine teeth nearly 1 to 



1^ times as broad as prasmaxillary band ; 



head not more than If times as long as 



broad, 4-7 times its distance from dorsal. 5. C. rrio'tisambicus, Peters, p. 232. 

 90 gill-rakers on anterior arch ; band of vo- 

 merine teeth as broad as prsemaxillary 



band ; head Ify times as long as broad, 9 



times its distance from dorsal .... 6. C. vineigueme, Blgr., p. 234. 



* The head is measured to the extremity of the occipital process. 

 t Caudal fin not included. 



