58 lEENS OF GREAT BEITAIN. 



indusium is a- membrane-like scale, and the clusters of 

 fructification form a continuous line on each side of the 

 midrib, and even with it. They are often very nume- 

 rous on the upper pinnse. 



The HoUy Pern is very difficult of cultivation. It is 

 called by some writers Aspidium LoncMtis, and by others, 

 Folypodium LoncMtis. 



2. P. aculedtum (Common Prickly Fern). — Fronds 

 rigid, linear, or lanceolate, twice pinnate ; pinnules acute, 

 running down the stem. This is quite a common fern, 

 one which is found almost throughout the kingdom on 

 hedgebanks and shady places, its dark green and hand- 

 some fronds contrasting with the brighter tinted Hart's- 

 tongue Fern, or the feathery grasses beside it. It grows 

 also in woods, but is seldom seen on the open heath, or 

 alpine hiU. It is a conspicuous plant, its fronds grow- 

 ing in circular clumps, and often two feet long. They 

 are at first nearly upright, but when fully grown, they 

 spread out like a coronal from a thick tufted stem. 

 They are lanceolate in form, and when luxuriant are 

 broad, but their outline varies much in different situa- 

 tions, and often even in plants of the same tuft. The 

 texture is rigid, the stalk usually short, and thickly, 

 clothed with membranous scales of a rust colour. In 

 April and May the fronds are some of the prettiest of 

 the green things of the hedgerow, their pale green 

 scrolls drooping downwards in most elegant forms. 

 By midsummer these are fully developed, while, by 

 the middle of August, the upper part of the fronds is 

 usually profusely crowded with dark masses of fruc- 

 tification, and neither summer's sun nor winter's frost 



