982 REPOTIT OP STATE GEOLOGIST. 



S. integrifolium Michx. Entire-leafed Rosin- weed. 



Found in prairies and open fields in rather damp soil. Its more 

 abundant distribution occurs in the northern part of its range. 



Flowering season, August and September. 



Tippecanoe (Cunningham); Kosciusko (Coulter); Cass (Hess- 

 ler); Laporte (Barnes); Jay, Delaware, Randolph, and Wayne 

 (Phinney); Gibson and Posey (Schneck). 



S. trifoltatum L. Whorled Rosin-weed. 



In rich, damp woods or about the shaded margins of lakes. 

 Chiefly northern in its reported range. 



Flowers from the middle of July until in August. 



Laporte (Barnes); Noble (Van Gorder); Round Lake (Deam); 

 Clark (Baird and Taylor); Jefferson (Barnes); Cass (Hessler). 



S. LACfNiATUM L. Compass-plant. Pilot-weed. 



In open or prairie regions, most frequently in rich, moist soils. 

 Abundant in the northern counties of its range, much less so in 

 the southern counties. 



Flowering season from July through September. 



Tippecanoe (Cunningham); Cass (Hessler); Jasper (Barnes); 

 Jay, Delaware, Randolph, and Wayne (Phinney); Gibson and 

 Posey (Schneck); Noble (Van Gorder); Elkhart (Barnes). 



S. terebinthinaceum Jacq. Prairie-dock. 



Found in several counties of the State in prairies and dry 

 woods, attaining its best development in sandy soils. Very much 

 more abundant in the northern counties of its range. 



Flowering season July until the middle of October. 



Vigo (Blatchley); Gibson and Posey (Schneck); Jay, Delaware, 

 Randolph and Wayne (Phinney); Elkhart (Barnes); Kosciusko 

 (Coulter); Tippecanoe (Wright); Hamilton (Wilson); Steuben 

 (Bradner). 



PARTHENIUM L. 



P. integrifolium L. American Fever- few. Prairie Dock. 



In dry, open places, reaching its best development in sandy 

 soil. The chief distribution is in the southern counties of the 

 State, not extending farther north than Laporte and Cass 

 counties. 



Flowering season from May until September. 



Floyd (Clapp); Laporte (Barnes); Clark (Baird and Taylor); 

 Gibson and Posey (Schneck); Tippecanoe (Cunningham); Cass 

 (Hessler); Vigo (Blatchley). 



