114 VERTEBRATE ANIMALS OF THE UNITED STATES 



Family 2. Elassomidae. — Pigmy sunfish. Body elliptical, com- 

 pressed, very small in size, with rather large cycloid scales; mouth 

 small, with strong teeth; upper jaw protractile; eyes large; cheeks and 

 opercles scaly; no lateral line; i dorsal fin: i genus. 



Elassoma Jordan. With the characters of the family: 2 species. 



E. zonatum Jord. Length 35 mm.; head 3; depth 3.5; color olive 

 green, with fine dots; sides with 11 vertical dark bands; rays of dorsal 

 fin IV to V, 9 or 10; anal III, 5; scales 18-38 to 42-19: southern Jllinois 

 to Texas and Alabama; in sluggish streams; not common. 



E. evergladei Jord. Scales very large, 27 to 30: swamps from Caroli- 

 nas to Georgia and Florida; common in the Everglades. 



Fig. 50. — Aphredoderus say anus (from Fishes of Illinois). 



Family 3. Centrarchidae. — The sunfish and black bass. Body 

 compressed and more or less shortened; mouth terminal; teeth in 

 villiform bands on the jaws, vomer, and often on the palatines, tongue 

 and hyoids; premaxillaries protractile; maxillaries usually with supple- 

 mentary bone; pseudobranchiae imperfect; lateral line present; but 

 I dorsal fin, with 6 to 13 spines, the spinous and soft-rayed portions 

 being confluent; 6 to 10 pyloric caeca: 12 genera and about 30 species of 

 fresh water fishes, all but one in the eastern States and all among the 

 most familiar food and game fishes. 



Key to the Genera of Centrarchidae 



ai Anal fin relatively long, almost as long as the dorsal. 



bi Spines of dorsal fin 11 to 13 i. Centrarchus. 



b2 Spines of dorsal fin 5 to 8 2. Pomoxis. 



3.2 Anal fin relatively short, much shorter than the dorsal. 



bi Spinous and soft-rayed portions of dorsal fin not separated 

 by a deep notch; depth of body usually more than two- 

 thirds the length. 

 Ci Hinder margin of tail convex. 



di Spines of anal fin 5 3. Acantharchus. 



d-2, Spines of anal fin 3. 



ei Spines of dorsal fin 9 7. Enneacanthus, 



e2 Spines of dorsal fin 10 8. Mesogonistius. 



