Cichlid Fishes of the Genus Tylochromis. 165 
1. Tylochromis microdon, sp. n. 
 Pelmatochromis lateralis (part.), Bouleng. Cat. Afr. Fish. iii. p. 885 
(1915). 
Depth of body 2} to 22 in the length, length of head 3. 
Snout from a little longer than to nearly twice diameter of 
eye, which is 34 to-nearly 5 in length of head, equal to or 
less than interorbital width or preeorbital depth. Maxillary 
not extending to below eye; teeth small; 3 series of scales on 
cheek ; 15 or 16 gill-rakers on lower part of anterior arch ; 
lower pharyngeal teeth mostly slender, compressed, hooked ; 
a triangular area on the posterior third of the plate with 
Fig. 1. 
A. Lower pharyngeal of Tylochromis microdon (xX 2) from a specimen 
240 mm. long. . 
B. Ditto of Tylochromis mylodon (xX 2) from a specimen 235 mm. long. 
moderately enlarged, rounded, blunt teeth. Dorsal SEV-RVI 
12-15; spines rapidly increasing to fifth or sixth, which is 
2 or a little more than 2 length of head, thence decreasing or 
subequal. Anal III 7-8; third spine strong, about $ length 
of head. Pectoral longer than head and reaching anal in 
the young, but not in the adult. Caudal scaly, truncate or 
slightly emarginate. Caudal peduncle longer than deep. 
Scales 33 to 35 in a longitudinal series, 6 between origin of 
dorsal and lateral line, 22 to 26 in upper lateral line, 22 to 24 
in lower, 2 between lateral lines. 
