i6 7 

 RUTACE^. Rue Family. 



Xiiuthoxylum Americaiium, Mill. Prickly Ash. 



In woods along streams and bordering lakes from the 

 Missouri valley eastward. 



POLYGALACE^E. Milkwort Family. 



Polygala verticillata, L. Whorled Milkwort. 

 On bluffs and prairies throughout the state. 



Polygala senega latifolia, T. & G. 



Common in the northern part of the Black Hills. 



Polygala alba, Nutt. White Milkwort. 



Common from the Missouri valley eastward and in the 

 Black Hills. 



EUPHORBIACE^. Spurge Family. 



Crotoii Texeiisis, (Klotzsch.) Muell. Texas Croton. 



Common in dry, sandy soils from the Missouri valley 

 westward. 



Euphorbia petaloidea, Engelm. White-flowered Spurge. 

 In sandy soil from the Missouri valley westward to 

 the Black Hills. 



Euphorbia Geyeri, Engelm. & Gray. Geyer's Spuige. 

 In dry soils from the Missouri valley westward. 



Euphorbia serpyllifolia, Pers. Thyme-leaved Spurge. 

 Common in the Minnesota, Sioux, and James valleys. 



Euphorbia serpens, H. B. K. Round-leaved Spurge. 



In the southern Missouri valley; Charles Mix county. 



Euphorbia Glyptosperma, Engelm. Ridge-seeded 

 Spurge. 



In dry soils throughout the state; the most common 

 species. 



Euphorbia maculata, L. Milk Purslane. 

 In the Sioux and James valleys. 



