250 Mr. C. T. Regan— Classification of 



2. Teeth conical or cuspidate, in 3 to 5 series ; frontal region 



humped ; maxillary exposed 3. Cyphotilapia. 



3. Teeth conical. 



a. Occipital crest not extending forward to anterior end of 



interorbital region. 

 a. Upper lateral line well separated from dorsal fin. 

 Fourth \ertebra with inferior apophyses ; lower 



jaw strongly projecting 4. Parachromis. 



Third vertebra with inferior apophyses ; lower 



jaw not or scarcely projecting 5. Pelmatochromis. 



li. Upper lateral line contiguous to dorsal fin. 



6. Nannochromis. 



b. Occipital crest extending forward in advance of interorbital 



region ; teeth small, forming broad bauds. 



7. Ilderochromis. 



B. Pharyngeal apophysis strong, ending in a liat triangular or ovate 

 articular surface; teeth conical; lower lateral line long. 



8. Tylochromis. 



II. Articular surface for upper pharyngeals formed by parasphenoid 

 in the middle and basioccipital at sides. 



A. Three anal spines. 



1. Teeth conical or compressed, with or without cusps, not 



incisor-like. 



a. Third vertebra with inferior apophyses. 

 Teeth conical, maiuly uniserial ; middle pairs 



more or less enlarged; maxillary narrow, 



curved 9. Ilemichromis. 



Teeth in 2 or more series, conical or compressed, 

 unicuspid, or outer bicuspid and inner tri- 

 cuspid , 10. Hajilochromis. 



b. Fourth vertebra with inferior apophyses. 

 Apophyses of fourth vertebra united below ; 



pharyngeal teeth stout, blunt 11. Saryochromis. 



Apophyses of fourth vertebra small, paired ; 



pharjTigeal teeth slender 12. SerranochroDiis. 



2. Teeth incisor-like, rather broad, entire or slightly notched. 



13. Steatocrauus. 



B. Four or more anal spines ; strong anterior canines. 



14. LamiU'oloyus. 



1. TiLAPiA, A. Smith, 1840. 



Regan, Ann. & Mag. Nat. Hist. (9) v. 1920, p. 37. 



This genus includes about 50 species from Africa and 

 Syria ; it corresponds to Boulenger's section I. (scales 

 cycloid or feeV)ly denticulate), with the following excep- 

 tions : — 



1. T. auromarginata [Otopharynx). 



2. T. avails {■=.HaplocIiromis moffati). 



