412 ME. G. A. BOFLENGEE ON A COLLECTION OF FISHES 



Dorsal XV 13 ; spines increasing in length to the last, which is f to ^ length of head ; 

 longest soft ray ^ to | length of head. Anal III 9-10 ; third spine longest, |- to i 

 length of head. Pectoral as long as head, reaching vertical of origin of anal or beyond. 

 Ventral reaching vent or anal. Caudal rounded. Caudal peduncle as long as deep. 

 Scales rugose, not or but very indistinctly denticulated, 34-37 ^ ; lat. 1. ^l. 



Males dark brown to blackish, the scales on the body pale greyish brown in the 

 centre ; dorsal, anal, pectoral, and caudal with a broad light edge (grey in spirit), anal 

 with round white spots. Female olive-brown above, yellowish beneath, with ill-defined 

 darker cross-bands ; vertical tins brown, with round darker spots. The smallest specimen 

 is brownish above (in spirit), with five rather irregular dark cross-bands, the first 

 across the nape ; lower surface of head and belly whitish ; dorsal, anal, and caudal 

 brown with dark spots ; a few white spots on the posterior part of the soft dorsal ; 

 pectoral blackish. Iris brown, with a gold or silver ring round the pupil. 



Total length 155 to 240 mm. 



Native name : Nchu. 



Two specimens. 



19. Paeatilapia thumbeegi Casteln. (Plate XLI.) 



A large Paratilapia of elongate form, usually with 17 dorsal spines, referable to 

 P. rohusta Gthr., a species known from Lake Nyassa, the Zambesi, and Mossamedes, 

 answers well enough to the description of Chromys tliwmbergi and Chr. ngamensis of 

 Castelnau (p. lo) to leave no doubt in my mind as to the propriety of adopting the 

 name P. thumbercji in preference to the later P. rohusta. 



1 here transcribe Castelnau's descriptions : — 



Cheomys thumbeegi. 



" Longueur totale, m. 30 ; corps un peu allonge ; pectorales non prolongees ; dents 

 assez grandes, serrees, aigues et un peu crochues, sur une rangee sur les cotes, et 

 plusieurs en avant ; epines de I'anale faibles. Dessus d'un brun noir, avec le dessous 

 du corps chatain ; caudale de la couleur generale ; dorsale grise, couverte de taches 

 arrondies, noires ; anale grise avec les pointes rouges ; toute sa surface est couverte 

 de taches arrondies, vertes ; pectorales verdatres, ainsi que les ventrales ; iris gris. 



"Dorsale, 17/13.— Anale, 3/9.— Ventrales, 1/5.— Pectorales, 15.— Caudale, 16." 



Cheomts kgamensis. 



" Poisson ovalaire allonge, ayant m. 33 de long; nageoire dorsale a 31 rayons, 

 dont les 17 premiers epineux ; la caudale, 16 ; I'anale, 3/9 ; les ventrales, 1/5 ; les 

 pectorales, 13. Les 14 derniers de la dorsale allant progressivement en s'allongeant. — 

 Couleur generale d'un vert fonce, devenant d'un gris obscur en arriere; nageoire 



