On the South' American Genera Retroculus, tOc. 41i 



N'l. — A lit'ii.sion itf the Stiit/h-A/iirrican Cichlid Genera 

 Jietroculu^, (io()|)li;i;,Mis, Ilitcrogramiiia, and iiiotoccus. 

 By C. T.vTE KKfiA.v, IJ.A. 



TiiK ^'fiura here dealt with arc distiugiiished from otlicr 

 Cichlidic l)v the foUowiii^^ eoinhiiiatiou of characters: — 

 Dorsal (in without notch between spinous and soft portions; 

 gill-rakcrs, if present, short or of moderate length, in small 

 or moderate number; anal fin with 3 spines ; teeth conical; 

 pneopcrculnm entire ; a compressed lobe on the upper part 

 of the anteiior branchial arch. 



riicir relations to each other may be shown by means of 

 the following synopsis: — 



I. Fir-t Lranchiid arch with the upper gill-rakers of the outer seiies 



running at the base ol' the lobe ; upper lateral line well separated 

 from the spinous dorsal Jietroculus. 



II. First branchial arch with the gill-rakers of the outer series, when 



developed, continued on to the free edge ot the lobe. 



1). XII-XIX t( 14; upper lateral line well separated 



frniii ihe spinous dorsal Geophagus. 



1>. XV-XVI 5-7 ; upper lateral line, if conii)ltte, 

 separated from the dorsal fin, for most of its 

 length, by only \ a series of scales Ilcteroyramynn. 



D. Vll-Vin 14-lo; lateral line more or less rudi- 

 mentary Biutoccus. 



I take this opportunity of gratefully acknowledging my 

 indebtedness to Dr. ¥. Steindachncr, who has given me 

 information as to the number of gill-rakers in Geophayus 

 pupjutterra, Prof. JJ. G. Wilder, who has sent me notes on 

 the type of Retrornlus Boulenyeri and has also permitted me 

 to examine the excised first branchial arch of the same 

 specimen, and Dr. It. Gestro, who has lent the type of 

 Geophagus Balzani. 



Retroculus. 



Jietroculus, Eigenni. it Bray, Ann. Ac. X. York, vii. 18^14, p. 014 ; 

 Pellegr. Mem. Soc. Zool. France, xvi. 1903, p. 181 (1904;. 



Body moderately elongate, compressed ; scales rather large, 

 ctenoid. Two lateral lines, the upper well separated from 

 the spinous dorsal. Mouth moderate; jaws ecjual ante- 

 riorly ; maxillary completely sheathed by the deep pncorbital ; 

 teeth conical, in bunds; no canines; cheeks scaly; pra- 

 operculum entire. Gill-rakers short, in moderate numl)cr; 



Ann. iii- Mag. A', lli.st. Scr. 7. Vol. xvii. \ 



