TILAPIA. 



225 



brown longitudinal band in its upper portion ; male with the mouth 

 and ventrals blackish (dark blue in life), and a few large bright ocellar 

 spots on the anal. 



Total length 115 millim. 

 Angola. 



1-2. Types. 

 3. Skel. 



Luciilla R. at Luenlla. 



Dr. W. J. Ansorge (C. 



59. TILAPIA WILLTAMSII. 



Ch'omis tvilliamsi, Giintli. Proc. Zool. Hoc. 1893, p. 621, pi. Ivi. fig. 0. 

 Tilapia williamsi, Bouleng. Tr. Zool. Soc. xv. 1898, p. 4, and Proc. Zool. Soc. 

 1899, p. 132 ; Pellegr. Mem. Soc. Zool. France, xv. 1901, p. 335. 



Depth of body equal to length of head, 3 times in total length. Head 

 twice as long as broad; snout broadly rounded, with slightly convex 

 upper profile, broader than long, much shorter than postocular part of 



Tilapia xvilliamsn. 

 Type, after Giiather (P. Z. S. 1893). 



head ; eye a little shorter than snout, 4 times in length of head, a little 

 less than interorbital width, equal to least depth of preeorbital ; mouth 

 broad, | width of head, with thick lips, extending to below anterior 

 border of e)e; teeth in 5 or 6 series, outer larger; in the upper jaw 

 the lateral teeth are conical and rather abruptly differentiated from the 

 others, which are bicuspid ; 52 teeth in outer series of upper jaw ; 

 4 series of scales on the cheek, width of scaly part equal to diameter of 

 eye. Gill-rakers short, 10 on lower part of anterior arch. Dorsal 

 XVII 8 ; last spine longest, nearly | length of head, | longest soft rays. 

 Anal III 7; third si)ine a little shorter than last dorsal. Pectoral f 

 length of head, not extending to origin of anal. Ventral reaching vent. 



