92 MR. G. A. BOULENGER ON A COLLECTION 



last, which is ^ length of head ; soft rays slightly longer, the last not produced. Anal 

 III 17 ; third spine \ length of head. Pectoral pointed, -§- length of head. Ventral 

 nearly reaching origin of anal. Caudal deeply emarginate. Caudal peduncle twice as 

 long as deep. Scales 44§ ; lat. 1. jp^jg- Brownish above, whitish beneath; a blackish 

 opercular spot; a lateral series of rather indistinct dark spots; dorsal greyish; other 

 fins yellow. 



Total length 97 millim. 



A single specimen, with the mouth and pharynx full of advanced embryos. 



The characters of the 3 species of Ectodus may be contrasted as follows : — 



E. descampsi, D. XIII-XIV 13-14. A. Ill 8. Sq. 34-35^; lat. 1. g=§- 

 Depth of body 3|-3| in total length. Snout slightly shorter than eye. 



E. melcmogenys. D. XIII-XIV 16-17. A. Ill 13. Sq. 43-44 ~; lat. 1. g=fj- 

 Depth of body 5-5^ in total length. Snout much longer than eye. 



E. longianalis. D. XV 15. A. Ill 17. Sq. 44f ; lat. 1. yr^- Depth of body 5 in 

 total length. Snout much longer than eye. 



Xenotilapia, g. n. 



Body moderately elongate ; scales ctenoid ; three lateral lines. Mouth small, very 

 protractile; upper jaw with, series of minute conical teeth; two mandibular teeth 

 turned outwards, in a single series ; maxillary concealed under the prseorbital when 

 the mouth is closed. A large papillose pad on each side of the pharynx, between the 

 gills. Dorsal with 14 or 15 spines, anal with 3. 



11. Xenotilapia sima, sp. n. (Plate XIX. fig. 5.) 



Depth of body 4 times in total length, length of head 3J. Snout very short and 

 deep, with very steep convex upper profile ; eye very large, oval, its diameter f length 

 of head and much greater than interorbital width ; mouth nearly straight, horizontal, 

 extending to below anterior border of eye ; 3 or 4 series of scales on the cheek ; 

 deciduous scales on the opercle. Gill-rakers very short, broad, truncate, 9 on lower 

 part of anterior arch. Dorsal XIV-XV 12 ; spines subequal from the fifth, ^ length 

 of head; longest soft rays f length of head. Pectoral acutely pointed, as long as head. 

 Ventral with the inner ray produced and reaching a little beyond origin of anal. 

 Anal III 11 ; third spine ^ length of head. Caudal with deep crescentic notch. 



Caudal peduncle twice as long as deep. Scales strongly ciliated, 40-41 j^-^ ; lat. 1. 21-22 . 



15-115 



