94 CEOMERinm 



1. CROMERIA NILOTICA. 

 (Plate XIV. fig. 3.) 



Boulenger, Ann. & Mag. N. H. (7) viii. 1901, p. 445 ; Swinnerton, Zool. Jahrb., Anat. 



xviii. 1903, p. 58, figs. 



Depth of body six and a half to eight times in the total length, length of head five 

 to six times. Snout rounded, projecting strongly beyond the mouth, the width of 

 which is about six times in the length of the head ; diameter of eye about five times 

 in the length of the head. Dorsal fin with 9 or 10 rays, 3 or 4 of which are 

 rudimentary, 5 branched, opposite to the space between the ventrals and the anal, 

 about twice as distant from the end of the snout as from the base of the caudal fin ; 

 longest rays three-fourths to four-fifths the length of the head. Anal fin with 9 or 10 

 rays, 3 or 4 of which are rudimentary, 5 branched, similar to the dorsal, nearly equally 

 distant from the ventrals and from the base of the caudal. Pectoral fin three-fourths 

 or four-fifths as long as the head, longer than the ventral. Caudal fin forked, with a 

 deep crescentic notch, the lobes pointed. Caudal peduncle once and a half to once 

 and two-thirds as long as deep, with a fold of skin above and below, which extends 

 from the caudal fin nearly to the dorsal and anal fins. 



Colourless, except a bright yellow stripe dotted with black along the dorsal line and 

 the lower edge of the caudal peduncle, and a blackish line along each side of the 

 caudal peduncle. 



Measurements (in millimetres). 



Total length 32 



„ „ (without caudal) 29 



Greatest depth of body 4 



Length of head 5 



Width of head 1| 



Longest ray of dorsal 4 



» anal 3J 



Length of pectoral 4 



Several specimens were obtained at Fashoda (2-3.01) and in Lake No (2.01) by 

 Mr. Loat. 



Many of the peculiarities of the cranium are due mainly to the enormous size of the 

 brain. This projects dorsally and separates the frontals widely from each other. 

 These bones therefore do not take any part in the roofing-over of the cranial cavity, 

 but, on account of their large size, they occupy nearly half of its side wall. Those otic 

 bones which are usually seen in the dorsal aspect are likewise shifted to the sides ; 

 apart from this, their relationships to one another are quite normal ; the opisthotic is 



