3o6 Field Museum of Natural History — Zoology, Vol. VII. 



Genus Apliredodervis Le Sueur. 



Body elongate; dorsal region elevated; mouth terminal somewhat 

 oblique; teeth in villiform bands on jaws, vomer, palatines, and ptery- 

 goids; alimentary canal ending in adult at the throat, the vent more 

 posterior in the young, moving forward from just behind ventral fins. 



Aphredoderus sayanus (Gilliams). Pirate Perch. 



Head 2.3 to 3.2; depth 3.1 to 3.5; D. hi, 9 to 12; A. 11, 6; scales 

 49 to 59. 



Body elongate, robust, the dorsal region elevated; head broad, 

 depressed, the profile concave; mouth moderate, oblique, maxillary 

 nearly reaching front of orbit, its length 2.7 to 2.9 in head; lower jaw 

 projecting; snout 2.8 to 3.4 in head; eye 3.5 to 4.3; dorsal fin nearer 

 tip of snout than base of caudal; caudal fin sHghtly forked; ventral 

 fins jugular in adult; lateral fins developed anteriorly; cheeks and 

 opercles with scales. 



Color dark oHvaceous to nearly black, with bluish tinge, speckled 

 with black; breast and belly yellowish; two blackish bars at base 

 of caudal. 



Length 2 to 4 inches. 



This fish inhabits lowland streams and ponds from Wisconsin to 

 New York and Texas. 



Salt Creek, Lyons, Illinois. 



Family Centra roll idfe. 



The Sunfishes. 



Body oval or ovate, compressed; anterior portion of dorsal fin of 

 5 to 13 spines; longest dorsal spine about Y^ length of longest 

 dorsal ray; body with weakly or scarcely ctenoid scales; side^ of 

 head with scales; mouth moderate or large; teeth in bands on jaws, 

 vomer, usually also on palatines and tongue; no canine-like teeth; 

 branchiostegals 6 or rarely 7 ; opercle ending in two flat points, or 

 prolonged backward in a black or partially black flap ; gill membranes 

 separate from the isthmus; premaxillaries protractile; pyloric coeca 

 5 to 10; air bladder without duct; ventral fins thoracic; caudal fin 

 emarginate or slightly forked; lateral line present. 



a. Anal fin more than half length of dorsal, with 5 to 8 spines. 



b. Dorsal fin with less than 10 spines, usually 5 to 8. Pomoxis, 307 



