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lated localities widely separated where certain species are found 

 within the State or of known stations within the State remote 

 from stations known beyond our borders clearly indicate that 

 these stations are the rearguard of a retreating flora. Iowa is 

 also the border land where the eastern flora terminates and the 

 western perceptibly begins. Thus situated, our State is unique, 

 and a study of its flora is interesting. 



OPHIOGLQSSAC&E. 

 Botrychium Virginianum Svvartz. Rattlesnake fern. Rich 

 woods. Common throughout Iowa, the individuals growing soli- 

 tary. 



Botrychium obliquum Muhl. Grape kern. Professor Arthur 

 reported this species from Floyd county and Professor Fink from 

 Fayette county, under the name of B. ternatum Swartz. 



osmundacm:. 



Osmunda claytoniana L. Interrupted fern. Rich woods. 

 Common throughout Iowa, often growing in large colonies. 



Osmunda regalis L. Royal fern. Wet soil, rare. Muscatine 

 county, Ferdinand Reppert. 



Osmunda cinnamomca L. Cinnamon fern. Rare. Musca- 

 tine county. Ferdinand Rep pert; Johnson county, Prof. Sliimek ; 

 Hardin county, Prof. Pammel. 



POLYPODIACE/E. 



Polypodium vulgar e L. Polypody. Rather infrequent in 

 northeastern and eastern Iowa. The usual habitat is crevices 

 of the limestone and sandstone cliffs. The species also occurs 

 in central Iowa, having been found along the Iowa river in 

 Hardin county and along the Des Moines river in Boone county. 



Adiantum pe datum L. Maiden hair fern. A very common 

 fern in our region, occurring in rich woodland soil throughout 

 the State. 



Pteris aquilina L. Bracken. Dry soil in open woods, fre- 

 quent in eastern Iowa and occurring in central Iowa, apparently 

 absent in the western portion. 



Cheilanthes lanuginosa Nutt. Infrequent. Found in north- 

 eastern Iowa, growing in mats on the dry faces of cliffs or in 



