DISCOGNATHUS. 



345 



1. DISCOGNATHUS DEMBEENSIS. 



Cliondrostoma dembeensis, Rilpp. Mns. Senckenb. ii. p. 16, pi. ii. fig. 4 (1837). 

 Gymnostomus ? demheensis, Hockel, Ilussegger^s Reise Egypt, iii. p, 329 (184G). 

 Discognatlius demheensis, Bouleng. Ann. & Mag. N. H. (7) xi. 1903, p. 54, and 



Fish. Nile, p. 181, pi. xlvili. fig. 1 (190'0- 

 ? Discognathis rothsddldi, Pellegr. Bull. Mus. Paris, 1905, p. 291. 



Body feebly compressed, its depth 4|- to Q\ times in total length. 

 Head moderately depressed, 1^ to IJ times as long as broad, its length 

 4J to 5 times in total length ; snout rounded, interorbital region nearly 

 flat ; eye supero-lateral, in second half of head, its diameter 4 (young) 

 to 7 times in length of head and about 2 to 3 times in interorbital 

 width ; width of mouth f to -| length of head ; lips covered with 

 granular papillae, the upper well developed, bordered by large papillae 



Fig. 259. 



Discognathus demheensis. 

 Lake Tsana (F. N.). 



forming a fringe ; lower lip forming a fold embracing a mental disk, 

 which is broader than long ; 2 small barbels on each side, not measuring 

 more than \ diameter of eye ; snout of breeding males studded with 

 numerous conical horny tubercles. Dorsal III 7, equally distant from 

 nostrils or anterior border of eye and from caudal, emarginate, longest 

 ray as long as or a little shorter than head. Anal II 5. Pectoral as 

 long as or a little shorter than head, widely separated from ventral, 

 which is situated below posterior half of dorsal. Caudal deeply 

 emarginate. Caudal peduncle 1\ to IJ times as long as deep. 



5-6- 



Scales 36-40 ^, 3-4 between lateral line and root of the ventral, 

 16-18 round caudal peduncle. Olive-green or brown above, yellowish 

 beneath ; a series of round black spots on the dorsal near its base. 

 Total length 160 millim. 



