TILAPIA. 531 



Coloration very variable, some specimens olive-brown, others brilliant vermilion on 

 the sides, others bright yellow with black markings and with the dorsal and candal 

 fins edged with red. Iris grey or dark hazel, with a red circle ronnd the pupil. 

 Young with or without dark cross-bands on the body and oblique dark bands on the 

 soft part of the dorsal fin, and with a blackish ocellar spot on the anterior part of 

 the soft dorsal fin. 



The largest specimen measures 320 millimetres. 



This species inhabits Lake Victoria. Over a hundred specimens were obtained by 

 Mr. Degen at Entebbe (June to Nov. 1905), five at Bunjako (5-14.11.05), and one at 

 Buganga (22.11.05). 



Tilapia variabilis is in many respects intermediate between T. nilotica and T. galilcea. 

 It differs from both in the longer caudal peduncle, and also, usually, in the smaller eye 

 and fewer soft rays in the dorsal fin. 



8. TILAPIA GALILiEA. 

 (Plate XCV.) 



Spams galilams, Artedi, in Hasselquist, Iter Pahest. p. 343 (1757). 



Tilapia pleuromelas, A. Dumeril, Arch. Mus. x. 1859, p. 253. 



Tilapia lateralis, A. Dumeril, 1. c. 



Tilapia macrocentra, A. Dumeril, t. c. p. 256. 



Chromis ? galilceus, Giinther, Cat. Pish. iv. p. 273 (1862). 



Chromis niloticus, pax^t., Giinther, t. c. p. 267, Proc. Zool. Soc. 1864, p. 490, and Petherick's Trav. 



ii. p. 216 (1869) ; Steindachner, Sitzb. Ak. Wien, lx. i. 1870, p. 964, pi. iv. fig. 1. 

 Chromis niloticus, Steindachner, Verh. zool.-bot. Ges. Wien, xiv. 1864, p. 226 ; Tristram, Faun. 



Palest, pi. xviii. fig. 1 (1884). 

 Cliromis tiberiadis, Lortet, Ann. Mus. Lyon, iii. 1883, p. 135, pi. vi. 

 Chromis microstomas, Lortet, t. c. p. 139, pi. viii. fig. 1. 

 Tilapia galilcea, Boulenger, Proc. Zool. Soc. 1899, p. 114 ; Pellegrin, Mem. Soc. Zool. France, xvi. 



1904, p. 311. 



Depth of body once and five-sixths to twice and a half in the total length, length of 

 head twice and two-thirds to three times. Snout with straight or convex profile, 

 broader than long, once (young) to twice and one-fourth the diameter of the eye, 

 which is contained three and one-fourth (young) to six times in the length of the head 

 and once (young) to twice and a half in the interorbital width ; width of praeorbital 

 greater than the diameter of the eye in the adult ; mouth small, not more than half 

 the width of the head, with thick lips, extending to below the nostril ; teeth very 

 small, in three (young) to ten series in each jaw, outer largest, 40 (young) to 120 in 



3y2 



