138 IOWA ACADEMY OF SCIENCES. 



propose the chan^^es. We have, therefore, used the 

 nomenclature of Gray's Manual,' as it fixes the species for 

 purposes of study. 



DISTRIBUTION. 



In the distribution of ferns, the paper by Prof. Shimek 

 has been used as well as the papers by Reppert, Miller, 

 Barnes and Witter, and the records given by Prof. Wheeler. 



A list of the Vascular Cryptogams of Iowa, as repre- 

 sented in the Herbarium of the Iowa State College, with 

 maps showing distribution according to this list, the list 

 included in the paper Iowa Pteridophyta by Prof. B. 

 Shimek, and the list in the paper, "A contribution to the 

 knowledge of the flora of southeastern Minnesota, by Prof. 

 W. A. Wheeler. 



ORDER EQUISETACEJ*:. 



Equisetiim arcense L. Sp. PI. 1061. 1753. 



This, the most common of the Horsetails, is found every- 

 where in Iowa on sandy banks and in black soils. 



Iowa: Ames— 7io//>, Stewart Ball, Bessei/. Ilodson, Carver; 

 Clermont— Walker; ^u^c?iimQ—Ueppcrt; Keokuk— Rolfs; 

 Marshalltown— .SVe/rv/r^; Hamilton County— /?o//"s; Grinnell 

 —Miss Williauis; Dubuque- Pa niniel; Boone— Pa)n met; 

 Emmet County— C rati i/. 



Equisetum sylvaticiDn L. Sp. PI. 1061, 1753. 



This has only been reported from one locality. The 

 fact of its occurrence along Skunk river is unusual. It 

 ought to be found in northeastern and eastern Iowa, where 

 the conditions for its occurrence are suitable. It w^as 

 found in damp, moist banks in a small piece of hemlock 

 woods near Bloomingdale, Wis., and in a tamarack marsh 

 near LaCrosse, Wis. 



Iowa: Jasper Qounty— Nor r is. 



4 Watson and Coulter Gray's Manual. 67 ^ 1890. [eth Ed. ] 



i 



