590 THE GEOLOGY OF MINNESOTA. 



[Natural drainage. 







SURFACE FEATURES. 



Natural drainage. The streams of this district are tributary to the 

 Minnesota river, excepting the southwest corner of Lincoln county which 

 lies within the basin of the Big Sioux river, and a small tract at the south 

 side of Lyon county, drained to lake Shetek and the Des Moines river. 

 Four great branches of the Minnesota river gather their waters partly or 

 wholly in these counties, namely, in their order from northwest to south- 

 east, the Lac qui Parle, Yellow Medicine, Redwood and Gottonwood rivers. 

 Only the second of these has its entire basin and course within this district. 



Lac qui Parle river receives the drainage from an area of about 60 square miles in northwest- 

 ern Lincoln county, and 210 square miles, approximately, in the west part of Yellow Medicine 

 county. Its principal head-streams in this district, in order from northwest to southeast are 

 Florida and Canby creeks, and the East branch of Lac qui Parle river, the last of which receives 

 the overflow of lake Hendricks on the state line. Between this basin and the Yellow Medicine 

 river, the creek called Stony run, tributary to the Minnesota river, drains a tract of about 150 

 square miles, lying wholly in Yellow Medicine county. 



The name of the yellow Medicine river, from the stream applied to the county, is the transla- 

 tion of the Dakota name Pejuta zizi, which signifies, according to Mr. T. M. Young, the long and 

 slender, bitter, yellow root of the moonseed (Mffnispermum Canadense), used by the Indians as a 

 medicine. This plant is found commonly along the banks and bluffs of streams throughout the 

 state. The basin of the Yellow Medicine river includes about 260 square miles in the central and 

 northeastern portions of Lincoln county; about HO square miles in northwestern Lyon county; 

 and some 200 square miles in Yellow Medicine county; its whole area being thus approximately 

 600 square miles. The farthest source of this river is lake Shaokatan, fifty miles southwest from 

 its mouth. Besides these tributaries, several small creeks, two to four miles long, join the Minne- 

 sota river in Yellow Medicine county, mostly produced by large springs which issue from the 

 bluffs of the Minnesota valley, or within the ravines which their outflow has channeled. 



The basin of the Hedwood river in this district embraces about 450 square miles, 125 of which 

 are in southeastern Lincoln county, the remainder being a belt that crosses Lyon county from 

 southwest to northeast. Lake Benton, the farthest source of the Redwood river, is sixty miles 

 from its mouth. The largest tributary of this river in its whole course is Three Mile creek, which 

 flows from the west line of Lyon county northeastward twenty miles, nearly parallel with the 

 Redwood river and three to five miles northwest from it. 



An area of about 240 square miles in southern and southeastern Lyon county is tributary, 

 by many creeks, to the Cottonwood river. The most northwestern branch of this river flows east- 

 ward nearly through the center of Lake Marshall township, being only two to three miles 

 southeast from the Redwood river. Another important branch rises in northwestern Murray 

 county, runs northeasterly between Rock lake and lake Yankton, and crosses the Winona & St. 

 Peter railroad close south of Amiret. 



Each of these four large tributaries of the Minnesota receives numerous small creeks in 

 these counties from the northeastern slope of the Coteau des Prairies, the base of which extends 

 from the southeast part of Lyon county northwest across this district, and enters Dakota at the 

 northwest corner of Yellow Medicine county. The waters that have sunk into the drift-sheet 

 upon the higher plateau-like portion of the Coteau, which extends fifteen or twenty miles far- 

 ther west, re-appear in springs along the great slope, about five miles wide with a descent of 250 

 to 500 feet, which forms the limit of this highland toward the northeast, notably distinguished 

 on the maps by its many small streams flowing northeastward. 



Lake Shetek, tributary to the Des Moines river, lies close south of this district in Murray 

 county, and its area of drainage extends into Lyon county at the middle of its south side so as 

 to include fifteen or twenty square miles of Rock Lake and Custer townships. 



