22 MR, G. A. BOULENGER ON [Jan. 20, 
MorMyrip&. 
1. PETROCEPHALUS SIMUS Sauv. 
bo 
. IsSICHTHYS HENRYI Gill. y, 
. MARCUSENIUS SPHECODES Sauv. 
m oO 
. MARCUSENIUS BRACHYHISTIUS Gill. 
CHARACINID&®. 
5, BRYCON/®THIOPS MICROSTOMA Gthr. 
6. ALESTES LONGIPINNIS Gthr. 
7. ALESTES INTERMEDIUS, sp.n. (Plate I. fig. 1.) 
Depth of body 3 times in total length, length of head 4 times. 
Head as long as deep, twice as long as broad ; snout shorter than 
diameter of eye; latter 22 to 2 times in length of head ; adipose 
eyelid indistinct ; interorbital width 3 length of head; width of 
mouth equal to diameter of eye; maxillary not extending quite 
to below anterior border of eye; 14 teeth (£) in the upper jaw, 
8 in the outer row of the lower jaw; length of lower border 
of second suborbital less than diameter of eye. Gill-rakers 
moderately elongate, 12 or 13 on lower part of anterior arch. 
Dorsal II 8, above ventrals, originating a little nearer end of 
snout than caudal, middle branched rays much produced (13 to 1 
as long as head) in the males. Adipose fin small, 13 to twice as 
distant from the rayed dorsal as from the caudal. Anal IIT 19-21, 
the outline very convex in the males. Pectoral shorter than head, 
not reaching ventral; latter produced into a long filament in the 
males. Caudal forked. Caudal peduncle a little longer than deep. 
Scales 33-34 a, 2 between lateral line and ventral. Silvery; a 
large black spot on the caudal peduncle and on the median rays 
of the caudal; latter yellow, blackish at the end; dorsal black 
and red. 
Total length 85 millim. 
Three specimens from the Kribi River. 
Intermediate between A. longipinnis Gthr. and A. tholloni 
Pellegr. Differs from the former in the smaller scales, from the 
latter in the smaller number of anal rays. 
8. ALESTES OPISTHOTHNIA, sp.n. (Plate I. fig. 2.) 
Depth of body 34 or 33 times in total length, length of head 4 
or 41 times. Head a little longer than deep, twice as long as 
broad; snout a little shorter than diameter of eye; latter 22 or 
3 times in length of head; adipose eyelid very feebly developed ; 
interorbital width 2 or nearly 3 length of head; width of mouth 
equal to diameter of eye or a little less; maxillary not extending 
quite to below anterior border of eye; 16 teeth (}) in the upper 
