ROCCUS — STRirED 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 in- 

 habiting fresh waters of the Mississippi Valley, the other being the striped 

 bass of the Atlantic (R. lineatus). 



ROCCUS CHRYSOPS (Rafinesque) 



WHITE BASS 



(Map C) 



Rafinesque, 1820, Tenth. 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; J., J., 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 3^ 

 greatest depth; depth caudal peduncle 1.2 to 1.3 in its length. "Color silvery, 

 tinged with golden below; sides with narrow dusky lines, about 5 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 con- 

 vex, 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-filaments, 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 nearly 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 collections (mainly from seine hauls of the fishermen), 

 made throughout 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 it has been absent also from all our collections in 

 the glacial lakes of northeastern 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 abundant with us in the 



