ELASSOMATIDA, — LXI. ts 
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 pseudobranchie ; 
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 
seven soft rays (all other perch-like fishes having one spine and five 
rays); C. rounded. Vertebre 29. Air bladder large. Pyloric 
ceca 12. One species, a small fish of nocturnal habits, abounding 
in sluggish grassy lowland streams throughout the Eastern U. 8. 
147. APHREDODERUS Le Sueur. (dodos, excrement ; 
d€pn, the throat.) 
295. A. sayanus (Gilliams). Pirate Prercu. Dark olive, 
profusely dotted with black ; two dusky bars at base of C. Head 
S -aepin se. YD. TI 11. sAsTE 6... Lat. l 48 to. 58. L. 6s) N.Y. 
to La., and N. to Minn. and Lake Erie; variable. (To Thomas 
Say, the entomologist.) 
Famitry LXI. ELASSOMATIDAS. (Tue Tryy Percues.) 
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; gil! rakers tubercle-like; lower pharyngeals narrower, 
with sharp teeth. B. 5. No lateral line; pseudobranchiz rudi- 
mentary. V. normal (I, 5). Dorsal small, with 4 spines; anal 
with 3; C. rounded. Vertebree 24. One genus, with two species, 
E. evergladei Jordan, of Florida, and the following. They in- 
habit sluggish, lowland waters of the E. U. S., and they are among 
the smallest of all fishes. 
148. ELASSOMA Jordan. (¢€Adoce@ya, a diminution.) 
296. E. zonatum Jordan. Olive green, finely speckled ; sides 
with 11 dark bars; a round black spot on side behind shoulder ; 
fins spotted ; a bar at base of C. Eye large; mouth small. Head 
3; depth 3}. D. V, 9. <A. III, 5. Scales 40-19. L. 1 to 14. 
S. Ill. to Ark. and La., in grassy brooks. (HLat., banded.) 
Famity LXI. CEHNTRARCHIDA. (THE Sun-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 terminal; teeth small; premaxillary 
protractile ; maxillary with a supplemental bone which is sometimes 
