ROCCUS — STRIPED BASS 319> 



Genus ROCCUS Mitchill 



(striped bass) 



Body deep and compressed; lower jaw projecting; no supplemental 

 maxillary ; lower margin of preopercle simply (not antrorsely) serrate or 

 entire; base of tongue with 1 or 2 patches of teeth; dorsal fins entirely 

 separate; anal spines 3, graduated in size; scales ctenoid. Species 2, 

 American, one inhabiting fresh waters of the Mississippi Valley, the other 

 being the striped bass of the Atlantic (R. lineatus) . 



ROCCUS CHRYSOPS (Rafinesque) 

 (white bass) 



Rafinesque, 1820, Ichth. Oh., 22 (Perca). 



G., I, 67 (Labrax multilineatus and notatus); J. & G., 529; M. V., 137; B., I, 128. 



(Morone multilineata) ; J. & E., I, 1132; N. 36; :T., 44; F., 63; F. F., I 3, 37: 



L., 29. 



Length 12 to 18 inches; body rather deep and compressed and back 

 elevated ; profile angled at nape; depth 2 . 6 to 2 . 9 ; greatest width about 

 i greatest depth ; depth caudal peduncle 1 . 2 to 1 . 3 in its length. "Color 

 isilvery, tinged with golden below; sides with narrow dusky lines, about 

 S above the lateral line, 1 along it, and a Variable number below it, 

 these sometimes more or less interrupted or transposed" (Jordan and 

 Evermann). Head subconic, flattened at sides, 3 . 1 to 3 .4; width of head 

 1 . 8 to 2 . 1 ; interorbital little convex, 3 . 4 to 4 . 1 ; nose longer than eye,. 

 3.4 to 3.8; mouth terminal, oblique, maxillary to middle of orbit, 2.2 

 to 2 .4 in head; lower jaw strongly projecting; gill-rakers long as gill-fila- 

 ments, X + 14. Dorsal IX-I, 13 or 14; longest spine about 2 in head; 

 base of soft dorsal 1.25 in base of spinous; caudal forked; anal III, 11 to 

 13, the spines graduated, first about half as long as second, and second 

 distinctly longer than third; ventrals § to vent; pectorals 1.6 to 1.9 in 

 head. Scales 8 or 9, 52-57, 13 or 14, very strongly ctenoid; lateral line 

 usually complete and nearlv straight; cheeks and opercles fully scaled, 

 rows 10 to 12. 



A species, in Illinois, of the larger rivers and bottom-land lakes, 

 "but found also in Lake Michigan. It has come to us in fifty-six col- 

 lections (mainly from seine hauls of the fishermen) , made through- 

 out the state from the Mississippi near Cairo to extreme northwest 

 Illinois, and thence to the Calumet River. We have not obtained it, 

 however, in the Wabash or Kaskaskia drainage; and jt has been 

 absent also from all our collections in the glacial lakes of northeast- 

 ern Illinois. It appears to be primarily a lake fish, and secondarily 

 one of the larger rivers, our coefficients for these waters being, 

 respectively, 2.8 and 1.7, and the collections from the smaller 

 streams of insignificant number. It has been much the most abun- 



