THE FERX BULLETIN 



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228. Equisetum laevigatum A. Br . Smooth 



Scouring Rush. Common ; in moist meadows. 

 New Jersey. Wisconsin and Louisiana to the 

 Pacific coast. The ecological forms Caespi- 

 tosum, elatum, polystachyon, scabrellum, ra- 

 mosum, and variegatoides have been described 

 in Fern Bulletin, Vol. XI. 



229. Equisetum litorale Kuhl. Shore Horsetail. 



Rare : in moist places. New Jersey, Pennsyl- 

 vania and Wisconsin northward; also in the 

 Old World from France and Austria north- 

 ward.. Variable; and often regarded as a hy- 

 brid. 



The following forms have been described in 

 Fern Bulletin, Vol. X. : arvensiforme 

 elatius, gracile, humile, prolifera, and vulgare. 



230. Equisetum palustre L. Marsh Horsetail. 



Rare: in wet grounds. Xew England, Illinois 

 and Washington to the far north : also in the 

 northern parts of Europe and Asia. 



231. Equisetum pratense Ehr. Shade Horsetail. 



Rare ; in cultivated fields and waste places. New 

 Jersey. Minnesota and Colorado northward ; 

 also in the colder parts of the old world. 



232. Equisetum scirpoides Mich. Dwarf Scouring 



Rush. Somewhat rare; on moist banks. Con- 

 necticut. Pennsylvania, Illinois. Nebraska and 

 British Columbia northward to Greenland and 

 Alaska ; also in Northern Europe and Asia. 



233. Equisetum silvaticum L. Wood Horsetail. 



Common : in moist shades. Virginia to Ne- 

 braska and northward to the Arctic Circle : also 

 in the colder parts of the old world. In Vol. 

 IX of the Fern Bulletin the following 



