128 MR. G. A. BOULEJSTGER ON THE ArEICA]S" AND [Peb. 7, 



a filament, extending beyond origin of anal. Anal III 9 ; third 

 spine a little shorter than longest dorsals. Caudal rounded. 

 Caudal peduncle a little longer than deep. Scales cycloid, 

 29 ^^ ; lat. 1. ^. Olive, a dark opercular spot ; two dark bars 

 across the upper surface of the snout ; a dark streak behind the 

 eye. 



Total length 95 millim. 



Lake Tanganyika. 



39. TiLAPIA BUBTTIKOFEEI. 



Chromis hiittikoferi, Hubreclit, Notes Leyd. Mus. iii. 1881, p. 66 ; 

 Steind. op. cit. xvi. 1894, p. 39.^ 



Teeth rather large (10 on each side in the outer row of the 

 upper jaw). Depth of body 2 to 2| in total length, length of 

 head 3 to 3|-. Snout as long as the eye, which is contained 3 

 times in length of head ; 5 or 6 series of scales on the cheek. 

 Gill-rakers short, 11 on lower part of anterior arch. Doi-salXiV- 

 XV 15-16. Pectoral as long as or a little shorter than the head, 

 not extending so far as origin of anal. Ventral prolonged into a 

 filament, extending beyond origin of anal. Anal III 10-11. 

 Caudal rounded (?). Scales cycloid, 29-30 ^-^ ; lat. 1. j^^- § dark 

 bars, the first two across the head, the last two on the caudal 

 peduncle ; these bars a little broader than the spaces between 

 . them. 



Total length 105 millim. 



St. Paul's Eiver, Liberia. 



40, TiLAPIA POI-YOENTRA. 



Tilapia poly centra, A. Dum. Arch. Mus. x. 1859, p. 254. 



Chromis polycentra, Giinth. Cat. iv. p. 270 (1862). 



Depth of body 2| in total length. 3 series of scales on the 

 cheek. 9 gill-rakers on lower part of anterior arch. Dorsal 

 XVIII 8. Anal III 7. Caudal rounded. Scales cycloid, 

 24 ^. Scales finely dotted with blackish ; soft dorsal with 

 alternatinp- series of dark and light spots and a large black spot in 

 front. 



Total length 100 millim. 



Gorea. 



41. TiLAPIA KIBKI. 



? Ctenochromis strigigena, Pfeffer, Jahrb. Hamb. wiss. Anst. x. 

 1893, p. 155, pi. ii. tigs. 5-8. 



Chromis Jcirkii, Giinth. Proc. Zool. Soc. 1893, p. 624, pi. Ivi. 

 fig. A (1894). 



? Chromis strigigena, Pfefl^er, Thierw. O.-Afr., Pische, p. 18, fig. 

 (1896). 



1 I am indebted to Dr. van Lidth de Jeude for notes supplementing the 

 descriptions quoted. 



