138 



CHAKACINIDJE. 



1. BRYCON^THIOPS MICROSTOMA. 

 Giinth. Ann. & Mag. N. H. (4) xii. 1873, p. 143 ; Bouleng. Ann. Mus. Congo, 

 Zool. i. p. 82, pi. xxxvii. fig. 1 (1899), and Poiss. Bass. Congo, p. 145 (1901). 

 Bracliyalestes mocqicardianus, Thominot, Bull. Soc. Philom. (7) x. 1886, p. 167. 

 Hryconcethiops boulengeri, Pellegr. Bull. Mus. Paris, 1900, p. 101. 



Depth of body 2|- to %\ times in total length, length of head 3^- to 3f 

 times. Head a little longer than deep, If to 2 times as long as broad; 

 snout broad, rounded, as long or a little shorter than eye, which is 1\ to 

 3^ times in length of head ; adipose eyelid much developed ; interorbital 

 width 2 to 2\ times in length of head ; maxillary extending to below 



2 



anterior border of eye or not quite so far; 14 teeth (M in upper jaw, 



8 or 10 (-=?) in lower ; lower border of second suborbital as long or a 

 little longer than diameter of eye. Gill-rakers slender, shorter than 

 gill-fringes, 15-17 on lower part of anterior arch. Dorsal II 8, nearer 

 occiput than adipose fin, its fifth ray above first of ventral ; longest ray 

 not longer than head. Anal III 17-20. Pectoral § to f length of head, 



Fig. 144. 



Bryconceihiops microstoma, var. boulengeri. 

 Congo (A. M. C). i. 



not reaching ventral. Caudal forked, with long pointed lobes. Caudal 

 peduncle 1-g to If times as long as deep. Scales 35-40 jf, 3 between 

 lateral line and root of ventral. Silvery, back olive or dark blue, with 

 a dark vertical bar on each side above the pectoral, or (var. boulengeri) 



