THE FERN PAKAUISE. 



5. 



THE ALPINE POLYPODY. 



Poly podium alpestre. 



PLATE 2, FJG. 5. 



(ROM its general resemblance to the Lady 

 Fern, the Alpine Polypody was for 

 many years mistaken for that species. 

 Even now some botanists think it should take 

 rank as a variety of Athyrium filix-fcemina. But 

 by almost general consent it is allowed to be a 

 Polypody, although it is not ' many-footed ' in 

 the sense in which the other Polypodies are. The 

 Lady Fern has very distinct covers to its clusters 

 of spore cases ; and Poly podium alpestre has none, 

 and consequently it bears what we have already 

 explained is the distinguishing mark of the Polv- 

 pody group. The fronds spring from a short and 

 erect root-stock, and, according to the circum- 

 stances of their growth, reach a length which 

 varies from one foot to three and a half. They 

 are lance-shaped somewhat broadly so tapering 



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