222 FIELD COLUMBIAN MUSEUM ZOOLOGY, VOL. V. 



2 in head, the last spine i^; middle rays of dorsal and anal fins pro- 

 duced, their tips in females reaching about middle of caudal, in 

 the larger males to within y^ of tip of caudal; pectoral fin !> in 

 head ; ventral fins produced, their tips reaching base of third anal spine, 

 the fin being slightly longer than the head; caudal fin rounded; 

 least depth of caudal peduncle 2 in head, its length i^ in its depth. 



Color dark brownish, about 5 dark vertical bands on posterior 

 half of the body; a black caudal spot about % of which is above the 

 lateral line ; soft dorsal, soft anal and caudal fin with some transparent 

 blotches; a few dark spots about X si ze f pupil on upper anterior 

 half of body, a few smaller dark dots on cheek and preorbital areas; 

 under side of head, breast, base of pectoral and ventrals nearly black. 



The larger males (9 inches in length) have a well developed nuchal 

 hump. Length about 12 inches. 



83. Thorichthys gen. nov. 



Type, Thorichthys ellioti Meek. 



Body deep, much compressed; mouth rather small; caudal fin 

 lunate, its outer rays produced into a filament; pectoral fin long and 

 pointed, about as long or longer than head; subopercle with a black 

 blotch, otherwise as in Cichlasoma. (0pwffxa> y to leap, ^0^?, fish.) 



On all specimens of this group collected by me there is no trace of 

 a nuchal hump. Individuals of the two species here listed from 

 southern Mexico are not large, as none of those collected by me exceeds 

 a length of 6 inches. These two species are very variable, though 

 they represent a quite distinct type of Cichlids. The following species 

 from Mexico and Central America apparently belong to this group : 



Thorichthys aureus (Gunther), Rio Motagua and at Yzabel, Guate- 

 mala. 



Thorichthys afjinis (Gunther), Lake Peten, Guatemala. 



Thorichthys fredrichsthali (Heckel), Rio San Juan, Nicaragua. 



Thorichthys rostratus (Gill & Bransford), Lake Nicaragua. 



Thorichthys longimanus (Gunther), Lake Nicaragua. 



KEY TO THE SPECIES OF THORICHTHYS. 



a. Dorsal spines high, longest i to 2 in head; PAGE 



cheeks with small blue spots. helleri 223 



aa. Dorsal spines lower, the longest 2f in head; 

 cheeks with black spots, some of which are 

 large as pupil ellioti 223 



