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a beautiful set of P. vulgar c varieties growing in the 

 British Isles, from native plants, not from mere garden 

 varieties. Dr. Christ contributed a fine set of varieties 

 collected in Switzerland, Germany, and Italy. With these 

 in my possession, it has been comparatively easy work to 

 determine the American specimens sent me, and also to 

 decide whether they have ever been named or not. Nearly 

 every year something new has been received, nor has the 

 tale yet been completed, as is evidenced by the new and 

 remarkable form discovered last fall by Miss Church at 

 Lake George, a description of which is included in the 

 accompanying list. 



Polypodium vulgare Linn, is one of the most easily 

 recognized of our ferns. The fronds are usually sub- 

 coriaceous, deeply pinnatifid, in some varieties fully pin- 

 nate, and even bipinnatifid, 5 to 50 cm. high, 2 to 10 cm. 

 wide, the pinnae faintly serrate to deeply laciniate, the 

 veins branched from once to four or five times, but in 

 one case at least simple, the sori round, medium to large 

 in size, situated generally in the middle of the pinnae at 

 the end of the lowest anterior branch of the vein, uni- 

 serial. It grows preferably on rocks or walls, but some- 

 times in shaly soil, and ranges as I have indicated from 

 Alaska through Canada to all the Northern States and 

 as far south as Arkansas and North Carolina. Of course 

 in these more southern localities it is only found among 

 the high mountains. 



In the Fern Bulletin for April, 1899. Mrs. E. G. 

 Britton gave a short account of the varieties of P. vulgare 

 then known in America, in which she mentioned four that 

 had been found here, viz., cambricum, cristatum, angus- 

 tum and rotunda-turn. Since that time a good many 

 others have been added to the list, and it seems desirable 

 that it should be brought down to the present time, in 

 order that those who are collecting may know what they 

 are liable to find. 



Prof. D. C. Eaton in " The Ferns of North America " 

 enumerated ten varieties described by Milde. Of these. 



