272 



CICHLID.E. 



4. PETROCHROMIS NYASS^. 



Bouleng. Ann. & Mag. N. H. (7) x. 1902, p. 70 ; Pellegr. Mem. Soc. Zool. 

 France, xvi. 1904, p. 352. 



Depth of body 2| times in total le'igth, length of head 3 times. 

 Head 1§ times as long as broad ; snout ranch broader than long, 

 1 1 times as long as eye, which is 4 times in length of head and 

 ]§ times in interorbital widrh; month extending to between nostril and 

 eye, upper lip very thick ; 4 series of scales on the cheek. Gill-rakers 

 very short, 13 on lower part of anterior arch. Dorsal XIX 8 ; spines 

 increasing in length to the seventh, which measures about ^ length 



Fig. 185. 



PetrochroDcis ni/assie. 

 Type. 



of head; longest soft rays as long as head. Anal III 7; third spine 

 thicker but a little shorter than longest dorsal. Pectoral a little longer 

 than head, nearly reaching origin of anal. Ventral produced, extending 

 beyond origin of anal. Caudal truncate, slightly cmarginate. Caudal 

 peduncle as long as deep. Scales feebly denticulate, very minute 



on breast and belly, 35 ^- ; lateral lines j"^. Olive-brown ; a black 

 opercular spot. 



Total length 185 millitn. 



Lake Nyassa. 

 1. Type. 



L. N 



ya.ssa. 



Prof. J. E. S. Moore {C). 



