EL ASSOM ATID^. — LXI, 113 



jaws, vomer, and palatines : premaxillary not protractile ; maxil- 

 lary simple ; preopercle and preorbital serrate ; opercle with a 

 spine ; bones of skull somewhat cavernous ; gill rakers tubercle- 

 like ; gill membranes slightly joined to isthmus ; no pseudobranchiae ; 

 gills complete. B. 6. Scales strongly ctenoid ; no lateral line. 

 Vent anterior, below the preopercle in adult, farther back in young, 

 its position changing by a lengthening of the rectum. Dorsal small, 

 with 3 or 4 spines ; anal with 2 ; ventrals without spine and with 

 set^en soft rays (all other perch-like fishes having one spine and five 

 rays) ; C. rounded. Vertebrae 29. Air bladder large. Pyloric 

 caBca 12. One species, a small fish of nocturnal habits, abounding 

 in sluggish grassy lowland streams throughout the Eastern U. S. 



147. APHREDODERUS Le Sueur. (a^oSoj, excrement ; 

 Stpj;, the throat.) 



295. A. sayanus (Gilliams). Pirate Perch. Dark olive, 

 profusely dotted with black ; two dusky bars at base of C. Head 

 3 ; depth 3. D. Ill, 11. A. II, 6. Lat. 1. 48 to 58. L. 6. N. Y. 

 to La., and N. to Minn, and Lake Erie ; variable. (To Thomas 

 Say, the entomologist.) 



Family LXI. ELASSOMATID^. (The Tiny Perches.) 



Body oblong, compressed, with large cycloid scales ; mouth small ; 

 teeth conic, strong, on jaws, a few on vomer ; upper jaw very pro- 

 tractile ; opercles entire ; gill membranes broadly united, free from 

 the isthmus ; gill rakers tubercle-like ; lower pharyngeals narrower, 

 with sharp teeth. B. 5. No lateral line ; pseudobranchiae rudi- 

 mentary. V. normal (I, 5). Dorsal small, with 4 spines ; anal 

 with 3 ; C. rounded. Vertebrae 24. One genus, with two species, 

 E. evergladei Jordan, of Florida, and the following. They in- 

 habit shiggish, lowland waters of the E. U. S., and they are among 

 the smallest of all fishes. 



148. ELASSOMA Jordan. (iXdaa-afia, a diminution.) 



296. E. zonatum Jordan. Olive green, finely speckled ; sides 

 with 1 1 dark bars ; a round black spot on side behind shoulder ; 

 fins spotted ; a bar at base of C. Eye large ; mouth small. Head 

 3; depths^. D. V, 9. A. IH, 5. Scales 40-19. L. 1 to 1^. 

 S. 111. to Ark. and La., in grassy brooks. (Lat., banded.) 



Family LXIL CENTRARCHID^. (The Sux-fishes.) 



Body more or less shortened and compressed, so that the regions 

 above and below the axis of the body are nearly equal and corre- 

 spond to each other. Mouth terniinal ; teeth smnll ; prciii;i\iilary 

 protractile ; maxillary with a sup])lemental bone which is somelimes 



•6 



