174 TWELFTH ANNUAL REPOET, 



EQUISETACE^. Horsetail Family. 



EQUISETUM, L. Horsetail. Scouring-Rush. 



[E. Telmateia, Ehrh., probably occurs in this state north of lake Superior.] 



E. arvense , L. Common Horsetail. 

 Common throughout the state. 



E. prateiise, Ehrh. Meadow Horsetail. 



Throughout the state, excepting perhaps far southward. Morrison county, Upham; 

 Stearns county. Uampbell; Saint Paul, Kelley. 



E. sylvaticuni, L. Wood Horsetail 



Throughout the state : common northward, but infrequent far southward. 



[E. palustre, L., will probably be found in the north part of the state.] 



E. liniosum, L. Swamp Horsetail. 

 Common, or frequent, throughout the state. 



E. Ifevig'atuni, Braun. Horsetail. 



Minneapolis, Simmons, Upham; Eed river, near Saint Vincent, Daivson, Scott. 

 South and west. 



E. liieiiiale, L. Scouring-Rush. SLave-Grass. 



Common throughout the state ; very abundant along the banks of the Minnesota 

 river. Parry. 



E. variegatuni, Schleicher. Horsetail. 



Throughout the state, excepting perhaps far southward. Near the Mississippi river, 

 Anoka county, Upham; Minneapolis, Simmons. Infrequent. 



E. scirpoitles, IVTichx. Horsetail. 



Eange like the last, also infrequent. Lapham. Deep woods, St. Croix river, 

 Parry. 



FILICES. Ferns. 



POLYPODIUM, L. Polypody. 



P. vulg-are, L. Common Polypody. 



Abundant, or common, through the north half of the state ; frequent southeast- 

 ward, on the rocky bluffs of the St. Cioix, Mississippi and Minnesota rivers, and their 

 tributaries ; rare south westward. 



ADIANTUM, L. JMaidenhair. 



A. peclatuiii, L. American Maidenhair. 



Frequent, in many places common or abundant, throughout the state. 



PTERIS, L. Brake or Bracken. 



p. aquilina, L. Common Brake. Bracken. Eagle Fern. 

 Common, or frequent, throughout the state. 



branches of the panicle, with, sometimes, one to three pairs of spikelets on the branch 

 below the terminal three. Fertile spikelets with the lower glume larger and coriaceous ; 

 the second narrower, thick, keeled, pointed or awned ; the third hyaline and empty; 

 the fourth or flowering glume hyaline and awned. Palet minute or none. T'asej/V 

 Grasses of U. S. 



