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EQUISETACE^, 



(HoKSETAiL Family.) 



Equisetum arvense, L. (Common Horsetail.) 

 Moist places. Very common. Oa the railroad beds, a prostrate, 

 much branched form occurs, caused by the continual passing of 

 trains, which prevents the plant attaining its ordinary height. 



Equisetum sylvatieum, L. 

 In shady places. Frequent. A very graceful plant. 



Equisetum limosum, L. 

 Open wet places. Frequent. 



Equisetum hyemale, L. (Scouring Rush.) 

 Near Cold Spring, Salem (Dr. G. A. Perkins) ; Methuen, on the 

 bed of the M. & L. R. R. ; Danvers, on the bed of the Newburyport 

 R. R. ; "moist woods, Lynn" (Bigelow's Fl. Bost., 1814). The 

 least common species. 



PILICES, 



(Ferns.) 



Note. — This order and the Ophioglossacefe have been rearranged to 

 conform to the "Systematic Fern List," but very recently (Oct., 1880) 

 published by Professor Daniel C. Eaton of New Haven. 



Polypodium vulgare, L. (Polypody.) 



Covering shaded rocks. Common. 

 Var. Cambricum (English authors). 



A specimen corresponding to this variety was found some years 



since, at Andover, by Mr. Jackson T. Dawson. 



Adiantum pedatum, L. (Maidenhair.) 

 Towns of the Merrimac valley, frequent ; and in small stations 

 elsewhere. 



Pteris aquilina, L. (Common Brake.) 

 In half shade on well drained soil. Quite common. A variety hav- 

 ing the fronds several times pinnate, but not ternate, is occasionally 

 met with; the same form is found near Boston (E. H. Hitchings). 



Woodwardia Virguiica, Smith. (Virginian Chain-Fern.) 

 Borders of ponds, extending its rhizomes under the water ; swamps, 

 etc. Frequent. 



Woodwardia angustifolia, Smith. (Narrow-leaved Chain- 

 Fern.) 



Magnolia swamp, Gloucester (J. H. S. and J. R.) ; "Essex county" 

 (memo. Dr. Chas. Pickering). Rare. 



