44 Mr. C. T. Regan — Classijication of 



pharyngeal triangular, with slender pointed uni- or bicuspid 

 teeth ; upper piuuyngeals sup|)Oited by a rather strong 

 apopiiysis with transverse articuhir surface formed by the 

 paraspheiioid. Occipital crest very strong, extending for- 

 wards to or in advance of anterior margin of orbits. 



Tanganyika and Upper Congo. 



Two species, C. frontosus and G. demeusii {Paratilapia 

 demeusii, Bouleng.). 



16. BOULENGKROOIIROMIS, Pellegr., 1904 

 (type Paratilapia microlepis, Bouleng.). 



Dorsal XVI-XVII 13-15. Anal III 9-10. Sailes cy- 

 cloid, small (75-90) ; two lateral lines. Mouth terminal ; 

 maxillary sligiitly exposed distally ; teeth small, in 4 or 5 

 series, conical (outer bicus[>id and inner tricuspid in the 

 young). Lower pharyngeal subtiiangular, with slender bi- 

 cuspid teeth. Occipital crest extending forward to end of a 

 median excavation of anterior part of frontals ; parietal crests 

 confluent with edge of frontals above middle of orbits; 

 ethmoid united with vomer by suture ; nasal bones slightly 

 expanded posteriorly ; prjemaxillary jjrocesses nearly reaching 

 frontals ; maxillary rami rather broad, of even width ; pos- 

 terior end of parasphenuid slifj;htly raised, bearing a pair of 

 transverse facets for articulation of upper pharyngeals. 

 Vertebrae 33 (16 + 17) ; third with a pair of inferior 

 aj)ophyses which unite below ; prrecaudals with parapophyses 

 from fourth ; ribs, except the first, on parapophyses. 



Tanganyika. A single species. 



17. Perissodus, Bouleng., 1898 (type P. microlepis, 



Bouleng.). 



Dorsal XVITI 10. Anal III 8. Scales cycloid, small 

 (65) ; two lateral lines. Differs from Boulengernchromis in 

 the dentition. Teeth in jaws uniserial, {^vf^ stout, with a 

 small cusp on each side superiorly. 



Tanganyika. A single species. 



18. IIaplociiuomis, Ililgend., 1888 

 (type Chromis ohliqitidens, Hilgend.). 



Dorsal XIII-XIX 6-13. Anal III (IV) 6-12. Scales 

 usually denticulate, large (28 to 45) ; two lateral lines. 

 Mouth terminal ; jaws opposed ; an outer series of bicuspid 

 or conical teeth and one or more inner series of smaller tri- 

 cuspid or conical teeth. Lower pharyngeal triangular ; teeth 



