132 ME. G. A. BOULBNGER OK THE AEBICAN AND [Feb. 7, 



lower part of anterior arch. Dorsal XVI 11 ; last spine longest, 

 |- length of head, a little shorter than soft rays. Pectoral pointed, 

 § length of head, not extending as far as origin of anal. Ventral 

 reaching vent. Anal III 9 ; third spine a little shorter than last 

 dorsal. Caudal rather deeply emarginate. Caudal peduncle Ig 

 as long as deep. Scales with finely denticulate edge, 35 -^ ; 

 lat. 1. ^^. Pale brown above, silvery white beneath ; five dark 

 brown cross-bars, broken up into large spots ; a small dark brown 

 opercular spot ; a large brown spot at base of caudal ; fins white. 



Total length 105 millim. 



A single specimen from Lake Nyassa. Collected by Miss M. 

 "Woodward ; presented by Miss S. C. McLaughlin. 



47. TILA.PIA WILLIAMSI. 



Chromis wilUamsi, Giinth. Proe. Zool. Soc. 1893, p. 624, pi. Ivi. 

 fig.C. 



Tdajna ivilUamsi, Bouleng. Tr. Zool. Soc. xv. 1898, p. 4. 



Teeth moderate, in 5 or 6 closely-set series in both jaws. 

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

 Snout with slightly convex upper profile, I5 diameter of eye, 

 which is 4 times in length of head and I3 in interorbital width ; 

 mouth I width of head ; maxillary extending to below anterior 

 border of eye ; 4 series of scales on the cheek ; large scales on the 

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

 Dorsal XVII 8 ; last spine longest, nearly | length of head, | 

 longest soft rays. Pectoral obtusely pointed, f length of head, 

 not extending to origin of anal. Ventral reaching vent. Anal 

 III 7 ; third spine a little shorter than last dorsal. Caudal 

 rounded, basal half densely scaled. Caudal peduncle shghtly 

 longer than deep. Scales finely denticulate on the border, 31 ^^ ; 

 lat. 1. ^. Dark brown, with scattered blackish spots ; a blackish 

 opercular spot ; a round blackish spot at the root of the caudal ; 

 fins grey, dorsal broadly edged with black ; two small round white 

 spots on the posterior part of the anal. 



Total length 105 millim. 



Lake Nyassa. 



48. TiLAPIA CALLIPTERA. 



Chromis caUipterus, Giinth. Proc. Zool. Soc, 1893, p. 623, pi. Iv. 

 fig. B (1894) ; Bouleng. op. cit. 1896, p. 916. 



Chromis subocularis, part., Giinth. 1. c. p. 621. 



Ctenochromis callipterus, Pfeffer, Thierw. O.-Afr., Fische, p. 19. 



TUapia calliptera, Bouleng. Tr. Zool. Soc. xv. 1898, p. 4. 



Teeth small, in 3 to 5 series in both jaws. Depth of body 2| 

 to 2|- in total length, length of head 2| to 3 times. Snout with 

 straight upper profile, 1| to 1| diameter of eye, which is 3| to 4 

 times in length of head and equal to or a little less than inter- 

 orbital width ; mouth f to | width of head ; maxillary extending 



