105 

 Horse-Tail Family. 



Equisetum arveiise, L,. Field Horsetail. 



In low sandy soil in the Minnesota and Sioux valleys, 

 and in the Black Hills. 



Equisetum sylvaticum, L. Wood Horsetail. 

 In moist woods in the Black Hills. 



Equisetum fluviatile, L. Swamp Horsetail. 

 In swamps in the Minnesota region. 



Equisetuni robustum, A., Br. Stout Scour ing-rush. 



In wet places throughout the state; less common than 

 the next. 



Equisetuni laevigatum, A., Br. Smooth Scouring- 

 rush. 



In low wet places; very abundant throughout the 

 state. 



IvYCOPODiACE^E. Club Moss Family. 



Lycopodium obscurum, L. Ground Pine. 

 In moist woods in the Black Hills. 



SELAGINELLACE^. The L,ittle Club Mosses. 



Selagiuella rupestris, (L.) Spring. Rock Selaginella. 

 On rocky slopes in the Black Hills. 



SPERMOPHYTES. SEED BEARING PLANTS. 



GYMNOSPERM^. GYMNOSPERMS. 



PINACE^E. 



Piuus poiiderosa scopuloruni, Englm. Western Yel 

 low pine. 



Throughout the Black Hills. 



Picea Caiiadeiisis, (Mill.) B. S. P. White Spruce. 



In the Black Hills, especially in the northern part. 



