188 



spine about 2 / 6 length of head. Anal III, 8 to 9; third spine a little shorter 

 than last dorsal. Pectoral 3 / 4 length of head, not reaching anal. Caudal 

 rounded. Caudal peduncle longer than deep. Grayish or blackish; males 

 with ocelli on anal fin. 



Remarks. — Three specimens, 80 to 95 mm. in total length. A 

 U-shaped, slightly raised ridge on the chest, reddish in color, is 

 well defined in two of the specimens, but is less evident in the 

 third. I have ascertained that the reddish color is that of the 

 muscles showing through the thin skin, and after comparison 

 with other species I have come to the conclusion that there is no 

 essential structural difference from them. 



Haplochromis mentatus, sp. nov. 

 Plate 10. 



Type. — No. 31523, Museum of Comparative Zoology, from Lake Edward; 

 115 mm. in total length. 



Description. — Depth of body 3 J /4 i n length, length of head 2 4 /b. Snout 

 V-/i diameter of eye, which is 4 in length of head, equal to interorbital width 

 or depth of cheek. Mouth moderately oblique; lower jaw projecting; maxillary 

 just reaching vertical from anterior edge of eye; teeth conical, triserial, outer 

 rather strong and set well apart, 46 in upper jaw, inner minute. Scales on 

 cheek in 4 series. Gill-rakers, 9 on lower part of anterior arch. Pharyngeal 

 teeth small. Scales in a longitudinal series, 33; from origin of dorsal to lateral 

 line, 6; between pectoral and pelvic fins, 5. Dorsal XV, 10; last spine 1 / i 

 length of head. Anal III, 9; third spine as long as last dorsal. Pectoral z /i 

 length of head, reaching origin of anal. Caudal subtruncate. Caudal pedun- 

 cle IV2 times as long as deep. Silvery; back darker; an indistinct lateral stripe 

 posteriorly; dorsal and caudal grayish, with small pale spots; lower fins pale. 



Remarks. — One specimen, differing from examples of H. 

 vittatus from Lake Kivu especially in the broader interorbital 

 region, l / 4 instead of 1 / 5 length of head. 



