248 MINNESOTA BOTANICAL STUDIES. 



Equisetum robustum A. BR. ; Engelm. Amer. Jour. Sci. 46 : 88. 



1844. Stout scouring-rush. 

 Reported from Thompson by Holzinger. 

 Herb. : There are no specimens in the herbarium. 



Equisetum hiemale L. Sp. PI. 1062. 1753. Common scouring- 

 rush. 



Frequent throughout the state. 

 Herb. : Many specimens. 



Equisetum laevigatum A. BR. ; Engelm. Amer. Jour. Sci. 46: 



87. 1844. 



Frequent in clay soil. 

 Herb. : Several collections. 



Equisetum variegatum SCHLEICH. Cat. PI. Helvet. 27. 1817. 



Variegated scouring-rush. 

 Infrequent. 

 Herb. : Butters, Detroit lake. 



Equisetum scirpoides MICHX. Fl. Bor. Am. 2: 281. 1803. 

 Sedge-like scouring-rush. 



Infrequent. 



Herb. : Ballard, Lake Kilpatrick ; Campbell, Grand Lake, 

 Stearns Co. 



Order FILICALES. 

 Family OPHIOGLOSSACE^). 



Ophioglossum vulgatum L. Sp. PL 1062. 1753. Adder's- 



tongue. 



Reported by Upham from Lake of the Woods, there are no 

 Minnesota specimens in the herbarium ; the plant, however, un- 

 doubtly occurs in the northern part of the state. 



Botrychium lunaria (L.) Swz. Schrad. Journ. Bot. 2: no. 

 1800. Moonwort. 



Infrequent, northern Minnesota. Cool, damp woods. 



Herb. : Cheney, Brule river ; Hibbard, Grand Marais ; Mac- 

 Millan and Sheldon, Lake of the Woods. 



Botrychium simplex E. HITCHCOCK, Amer. Jour. Sci. 6: 103. 



1823. Little grape-fern. 



Reported by Upham from Thompson, Carlton Co. 

 Herb. : No specimens from Minnesota. 



