38 MOEMYEID^. 



3. PETROCEPHALUS KEATINGIL 



(Plate VIII. fig. 2.) 



Boulenger, Ann. & Mag. N. H. (7) viii. 1901, p. 444. 



Depth of body two and four-fifths to three times in the total length, length of head 

 four to four and one-third times. Head as long as deep, twice as long as broad; 

 snout very short, one-sixth or one-seventh the length of the head, rounded, projecting 

 beyond the mouth ; mouth situated below the eye, its width two-sevenths the length 

 of the head; teeth bicuspid, 16 in the upper jaw, 26 in the lower ; nostrils close 

 together, on a level with the lower border of the eye ; eye large, longer than the snout, 

 its diameter one-fourth the length of the head, equal to the interocular width. 

 Dorsal fin with 25 rays, originating above the fifteenth ray of the anal, its length twice 

 in its distance from the head ; anterior rays longest, the fin pointed in front. Anal 

 fin with 38 or 39 rays, equally distant from the base of the ventral and from the base 

 of the caudal, or a little nearer the latter, the anterior rays longest. Pectoral fin 

 pointed, four-fifths the length of the head, twice as long as the ventral and extending 

 beyond the vertical of the base of the latter. Caudal fin scaled at the base, with 

 pointed lobes. Caudal peduncle twice and a half as long as deep, two-thirds the 

 length of the head. 41 to 44 scales in the lateral line, 37^ in a transverse series on 



13 . 



the body, g^g m a transverse series between dorsal and anal, 10 or 12 round the caudal 

 peduncle. 



Coloration silvery, the back and the anterior rays of the dorsal darker. 



Measurements (in millimetres). 



Total length (without caudal fin) 98 



Greatest depth of body . . 33 



Length of head 24 



Width of head 12 



Length of snout 3^ 



Diameter of eye 6 



Interocular width 6 



Width of mouth 7 



Length of caudal peduncle 1(5 



Depth of caudal peduncle 6| 



Length of pectoral fin 20 



This species, named in honour of the Director of the Government Medical School 

 at Cairo, was founded on two specimens, of the same size, obtained in a kore at 

 Fashoda by Mr. Loat between March 14th and 31st, 1901. A third specimen was 

 obtained in the White Nile, between Khartum and the Sobat by Mr. Zaphiro in 

 January or February 1904, and forms part of the collection presented to the British 

 Museum by Mr. W. N. McMillan. 



