IIG TELEOSTEI: ACANTHOPTERI. — XX. 



154. ENNE ACANTHUS (iill. (tuvta, nine; uKovda, spine.) 



a. Depth usually more than half leiij,'th; opercular spot large, more thaa 

 half eye. 



303. E. obesus (Hainl). Olivaceous, witli 5 to 8 distinct dark 

 cross-bars ; spots on hody and fins poldcn or jmrplish ; cheek with 

 lines and spots; a dark Itar Iwlow eye ; cheek with 4 rows of .scales ; 

 lateral line nsnally incomplete ; fins moderate, sj)ine of V. not 

 reaehinj,' vent. Head 25; depth IJ. D. IX, 10. A. Ill, 10. 

 Scales 4-32-10. L. 4. Mass. to Fla., common coastwise. (Lat., 

 fat.) 



aa. Depth usually less than half length; opercular flap small, bordered with 

 pearly and blue. 



304. E. simulans (Cope). Dark olive, young faintly barred ; a 

 dark bar below eye; ^ with head, body and vertical fins with 

 round sky-blue spots; 9 duller, with lower fins and larger, faint 

 spots ; lateral line usually complete. Head 2| ; depth 2^. D. IX, 

 10. A. Ill, 9. Scales 3-30-9. L. 5. N. J. to S. C, com- 

 mon coastwise; (number of spines sometimes variable). (Lat., 

 resembling.) 



305. R eriarchua (Jordan). Olivaceous; vertical fins with 

 round pale spots ; lateral line incomplete ; fins very large, espe- 

 cially A., which is reached by the ventral spines ; scales on cheek, 

 in 3 rows. Head 2}; depth 2J^. D. X, 9. A. IV. 8 (in typical 

 example probably abnormal). Scales 4-33-10. L. 3. Wis. to 

 Mo.; two specimens known. («pt, an intensive particle; dpxos, 

 anus.) 



155. MESOGONISTIUS (Jill, (^iaos, middle; ywvia, angle; 



ioTiov, sail.) 



306. M. chaetodon (Baird). Hody sulxjrbicular, the mouth 

 very small, tlu- fins high. Straw-color, with dark clouds ; 6 to 8 

 irregular, sharply-defined black bars across body and fins, the first 

 bar through eye. Head 3; depth 1§. D. X, 10. A. Ill, 12. 

 Scales 4-28-10. L. 3. N. J. to Md., in sluggish streams; hand- 

 somest of the sun-fishes. (A genus of fishes.) 



156. LEPOMIS Rafinesque. Sr.v-Fi!*nES. (IchthcUs, Pomolis, 



and Apomotix Ilafinesipie.) 

 (A large genus, one of the most difficult in our fauna, as the 

 species are subject to great individual variations, esjjeciallv with 

 age. On the other band the numlM'rs of scales and fin-ravs are 

 es.sentially alike in all, and nearly all the tlistinctive eliara<'ters are 

 subject to intergradation. Tlu- sj)ines are generally higher in the 

 young, while the '• i-ar-llap " is fully developed only in the adult.) 

 (Xfirif, scale ; rroi/xa, ojiercle.) 



