154 CHAEACINIim 



broad, upper profile deeply concave ; snout short, once and three-fourths to twice 

 as broad as long, a little longer than the eye in the adult, a little shorter in the young, 

 projecting slightly beyond the mouth ; diameter of eye three and a half (young) to six 

 times in length of head ; a narrow adipose lid in front of and behind the eye ; inter- 

 orbital width twice and one-fourth to twice and a half in length of head ; width of 

 mouth twice and one-third to three times in length of head. Gill-rakers short, fine, 

 closely set, about 50 on lower part of anterior arch. Dorsal fin with 17 to 20 rays, 

 3 to 5 of which are unbranched ; anterior branched rays more or less produced, often 

 longer than the head ; the fin originating behind the vertical of the base of the ventral 

 and nearer the root of the caudal than the end of the snout. Adipose fin moderately 

 large, its base one-half to four-fifths its distance from the rayed dorsal. Anal fin with 



25 to 31 rays, 3 or 4 of which are unbranched ; anterior rays forming a produced, 

 pointed lobe, measuring one-half to two-thirds the length of the head. Pectoral fin 

 three-fifths to three-fourths the length of the head, as long as or slightly shorter than the 

 ventral, reaching, or nearly reaching, the base of the latter. Caudal fin deeply forked, 

 with acutely pointed lobes. Caudal peduncle as long as deep or slightly deeper than 

 long. Scales 77-90 -j—, 17 to 21 between the lateral line and the base of the 

 ventral fin. 



Coloration silvery, the back greenish or purplish grey ; pectoral fin white, other fins 

 grey, usually with some bright red on the ventral, the anal, and the lower lobe of the 

 caudal ; adipose fin sometimes edged with black ; iris silvery. Young often with dark 

 longitudinal lines running between the series of scales. 



The largest specimen in Mr. Loat's collection measures 450 millimetres, but 

 specimens were observed at Mangara and at the mouth of Lake No measuring between 

 550 and 600 millimetres. A specimen from Khartum, in Petherick's collection, 

 is 480 millimetres long. 



C. citharus is known from the Lower Nile, the Upper Nile, the Blue Nile, the 

 White Nile, the Chad Basin, the Senegal, the Gambia, and the Niger. It has been 

 recorded from Lake Rudolf*. 



I have examined the following specimens : — 



1 Lower Nile.— Ruppell, 1833. 



1 Nile near Cairo.— Capt. Flower, 19.8.04. 



1 Biba, Lower Nile.— Loat, 14.9.99. 



2 In a backwater o£ the Nile, near Id. of Arko, Nubia. — Loat, 17.4.00. 



3 Khartum.— Petherick, 1862. 



5 Wad Medine, Blue Nile.— Loat, 5.10.01. 



26 Mangara, White Nile.— Loat, 3.1.01. 



GUnther, Proc. Zool. Soc. 1896, p. 223. 



