84 



POLYPODIUM ALPESTRE. Alpine Polypody. TAB. XLIX. 



Fronds lanceolate, bipinnate : pinnules linear-lanceolate, pinna- 

 tifid with obtuse sharply serrated lobes. 



Polypodium alpestre, Koch. Sprengel. Moore, Handb. 50. Pseud- 

 athyrium alpestre, Newman, Hist. Brit. Ferns, 199. 



This fern, a native of most parts of northern and central Europe, 

 does not seem to have been recognized as a British species, until 

 after its discovery in the Highlands of Scotland in July 1841, by 

 Mr. Watson; having been previously overlooked as an alpine 

 variety of Athyrium Filix-famina, which, though of less elegant 

 habit, it somewhat resembles at first sight. Its mountain habitats 

 render it one of local occurrence, but it appears from the observa- 

 tions of recent botanists to be far from sparing in its distribution 

 in North Britain. The rhizoma has a tendency to spread and 

 branch in a decumbent position, and the description to the con- 

 trary, given by some botanists, has probably originated from their 

 acquaintance with its habit being confined to plants growing in 

 situations not admitting of its natural development, or otherwise 

 to young specimens. The fronds are produced in circular tufts 

 from each crown, and vary in height from six inches to three feet, 

 according to age or luxuriance. The rachis is leafy almost to the 

 base, which is more or less thickly covered with broad pointed 

 brown scales. The small circular sori generally spring from the 

 lower anterior branch of the lateral veins of the pinnules, near the 

 sinuses between the lobes, but occasionally are more numerous, and 

 in such case become confluent in maturity. 



I am only familiar with this fern, so far as its cultivation is con- 

 cerned, as a continental species, and have not had an opportunity 

 of examining many specimens of British growth ; but traces of an 

 indusium are undoubtedly present occasionally, a circumstance that 

 probably led several European botanists to place it in the genus 

 Aspidium. 



The Alpine Polypody succeeds well under the same treatment 

 as the Lady Fern. 



Pseudathyrium flexile, Newman, Hist. Brit. Ferns, 203, may be, 

 as has been suggested, only a variety of alpestre, but if so it is a 

 very elegant one. The question of distinction as a separate species 

 must depend upon subsequent observation, but there is reason for 

 considering it such. 



