201 CICHLID^E. 



38. TILAPIA CHRISTYL sp. n. 

 Depth of body 2\ to 24- times in total length, length of head 3f to 

 3f times. Head nearly twice as long as broad ; snout with convex 

 upper profile, a little broader than long, as long as or a little shorter 

 than postocular part of head ; eye 4 times in length of head, If times 

 in interorbital width, equal to piseorbital depth ; mouth § width of head, 

 extending to between nostril and eye ; teeth in 4 series, outer largest, 

 40 to 50 in upper jaw, and separated from the others by a rather wide 

 interspace ; 3 or 4 series of scales on the cheek, width of scaly part equal 

 to diameter of eye. Gill-rakers very short, 9 or 10 on lower part of 

 anterior arch. Dorsal XVI-XVI1 12-13; last spine longest, \ length 

 of head ; longest soft raysf to f length of head. Anal III 9-10 ; third 

 spine nearly ^ or f length of head. Pectoral as long as or a lit;le 

 longer than head, not reaching vertical of origin of anal. Ventral 

 produced into a filament, not reaching origin of anal. Caudal rounded, 

 scaled nearly all over. Caudal peduncle much deeper than long. Scales 



3—'^ . 21— °S 



cycloid, 30-31 y^h > lateral lines ^j^. Brownish; the scales on the 

 sides dark brown or blackish at the base ; six rather indistinct dark 

 cross-bars on the body ; a black opercular spot ; spinous dorsal with 

 large brown spots; a large black spot at the base of the anterior rays of 

 the soft dorsal, followed by blackish spots forming oblique streaks or a 

 network ; caudal with round light spots in a brown network. 



Total length 180 millim. 



Upper Congo. — Types in Congo Museum, Tervueren. 

 1. One o£ the types. Stanley Falls. Dr. C. Christy (C). 



39. TILAPIA BILINEATA. 



Pellegr. Bull. Mus. Paris, 1000, p. 276 ; Bonleng. Poiss. Bass. Congo, p. 470 

 (1901) ; Pellegr. Mem. Soc. Zool. France, xvi. 1901, p. 325, pi. v. fig. 1. 



Depth of body 2^ to 2-f times in total length, length of head 3 to 3| 

 times. Snout with slightly convex upper profile, 1^ to 1^ times as long 

 as eye, as long as or a little shorter than postocular part of head ; eye 

 3| to 4 times in length of head, a little less than interorbital width; 

 mouth f width of head, extending to between nostril and eye ; teeth in 

 4 to 6 series, outer largest, 50 to 78 in upper jaw ; 3 or 4 series of scales 

 on the cheek. Gill-rakers short, 10 on lower part of anterior arch. 



