TILAPIA. 255 



diameter of eye. Gill-rakers large, falciform, 8 to 10 on lower part of 

 anterior arch. Dorsal X V-XVI 10-11 ; last spine longest, | to f 'length 

 of head, about f length of soft rays. Anal III 8-9 ; third spine shorter 

 and stronger than longest dorsal. Pectoral a little shorter than head, 

 reaching vertical of origin of anal. Ventral reaching vent or origin 

 of anal. Caudal densely scaled, rather deeply emarginate. Caudal 

 peduncle 1^ to 1| times as long as deep. Scales finely denticulate, 

 33-35 joijx5 lateral lines i^zjy- Silvery, brownish on the back; some 

 blackish spots or a black stripe above the upper lateral line ; a blackish 

 stripe may be present along the side of the body and above the 

 lower lateral line ; dorsal and caudal chequered with blackish between 

 the rays, the spots sometimes forming oblique stripes on the soft 

 dorsal. 



Total length 195 millim. 



Lake Nyassa. 



1. Type. L. Nyassa. Sir H. H. Johnston (P.). 



2. Ad. Between Koiidowe and Karonga. A. Whyte, Esq. (0.) ; 



Sir H. H. Johnston (P.). 

 3-4. Ad. L. Nyassa. Prof. J. E. S. Moore (C). 



5. Skel. 



6. Hgr. „ Capt. E. L. Rlioadcs (P.). 



85. TILAPIA ROSTRATA. 



Bouleng. Proc. Zool. Soc. 1899, pi. xii. fig. 1 ; Pellegr. Mem. Soc. Zool. France, 

 xvi. 1904, p. 344. 



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

 times. Plead 2^ times as long as broad ; snout long and pointed, with 

 slightly convex upper profile, much longer than broad, longer than 

 postocular part of head, twice as long as eye, which is 4| to 4| times 

 in length of head and equals ^ or once interorbital width or prseorbital 

 depth ; mouth f to § width of head, extending to between nostril and 

 eye ; teeth small, in 4 series, 54 to 70 in outer series of upper jaw; 3 

 or 4 series of scales on the cheek, width of scaly part equal to or a little 

 less than diameter of eye. Gill-rakers rather long, 16 to 21 on lower 

 part of anterior arch. Dorsal XV-XVl 11 ; last spine longest, ^ to f 

 length of head, a little shorter than soft rays. Anal III 9 ; third spine 

 stronger but a little shorter than last dorsal. Pectoral f length of 

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



