26 ACANTHOPTEETGII. 



37. Cichlosoma labiatum, GUnth., 1864. 



Cichlosoma labiatum, Regan, Ann. Mag. N. H. (7) xvi. 1905, p. 319. 



Hab. Lakes Managua and Nicaragua {Dow). 



Section 4. Thoeichthys, Meek, 1904. 



Very similar to AstatJieros in form and dentition, but with tiie dorsal and anal fins entirely scaleless and the 

 caudal truncate or slightly emarginate, usually with pointed lobes. Dorsal XV-XVII 8-12. Anal VI- 

 IX 6-9. 9 to 12 gill-rakers on the lower part of the anterior arch. The coloration of the three species 

 of this group may be described thus : — About six dark cross-bars, the third bearing a blackish blotch on 

 or below the lateral line; suboperoulum usually blackish; head and anterior part of body with blue 

 spots ; vertical fins dusky, usually with light spots. 



Synopsis of the Species. 



Pectoral extending to above origin of anal 38. caUolepis- 



Pectoral extending to above middle anal spines 39. aureum. 



Pectoral extending to first branclied ray of anal 40. affine. 



38. Cichlosoma caUolepis, Regan, 1904. (Tab. li. fig. 2.) 



Cichlosoma caUolepis, Regan, Ann. Mag. N. H. (7) xvi. 1905, p. 321. 

 Hob. Mexico, San Domingo de Guzman [Bidler). 



39. Cichlosoma aureum, Giinth., 1862. 



Cichlosoma aureum, Regan, Ann. Mag. N. H. (7) xvi. 1905, p. 320. 



Hah. SouTHEEN Mexico, Eio Papaloapam {Gadow, Meek), San Domingo de Guzman 

 and Eio de Sarabia (i^^Wer) ; Guatemala, Lake Yzabal and Rio Motagua (Salvin). 



40. Cichlosoma affine, Giinth., 1862. 



Cichlosoma affine, Regan, Ann. Mag. N. H. (7) xvi. 1905, p. 321. 

 Eab. Guatemala, Lake Peten (Salvin). 



Section 5. Paeapetbnia, Regan, 1905. 



The anterior pair of teeth in the upper jaw and the two on each side of the anterior pair in the lower are more 

 or less strongly enlarged and canine-like. The mouth is usually larger, more oblique and more pro- 

 tractile than in other groups of Cichlosoma, the length of the lower jaw or of the proimaxillary spines, 

 from the anterior edge of the upper jaw, measuring from f to a little more than | the length of the head. 

 The upper profile of the snout is straight ; the told of the lower lip is continuous or subcontiuuous. The 

 dorsal fin has XV-XVIII 8-13 rays and posteriorly has a scaly sheath at the base and a short series of 

 scales on each intorradial membrane; the anal has IV-IX 7-10 rays; the pectoral is shorter than the 

 head ; the caudal is rounded. 



In addition to the thirteen species from Mexico and Central America, there are two, 

 the most generalized of the group, C. tetracantiius and C. adspersuin, from Cuba and 



