250 
TEAVELS IN CENTEAL AEEICA. 
the length of the head thrice and one-fourth or thrice and two- 
thirds ; the diameter of the eye is somewhat less than the width of 
the interorhital space^ one-half of the length of the snout^ and two- 
fifths of that of the postorbital portion of the head. Intermaxillary 
with nineteen j mandible with fourteen_, teeth on each side. Cheek 
quite naked, the suhorbital ring being narrow. Operculum with 
radiating striae, twice as high as long. The origin of the dorsal 
fin is nearer to the root of the caudal than to the extremity of the 
snout ; it is higher than long ; anal fin somewhat longer than high; 
caudal with the lobes rounded, two-thirds as long as the head ; the 
pectoral as long * as the ventral, rather more than half as long as 
the head; the ventral terminates at a great distance from the 
vent. Uniform silvery; dorsal rays with some faint dots ; caudal 
with five or six rather irregular transverse series of round black 
spots. 
The two specimens are six and a half inches long. 
Ichthyhorus besse, Joannis. {Besse.) 
As we have mentioned above, this species appears to have much 
larger scales. Joannis found his specimens at Thebes, and the 
species has not been rediscovered since his time. 
Cor eg onus niloticus, Joannis. 
I take this opportunity of directing the attention of travellers to 
a small fish, which is evidently distinct from all the other known 
species of tropical Africa. I am not aware that it exists in any 
