138 



BRITISH FERNS 



twice-divided fronds are very fragile, as are the slender stalks 

 and their texture generally. They are perfectly deciduous with one 

 exception, viz. sempervirens. It is widely distributed, but is most 

 common in hilly districts in the north, where it is found sometimes 

 in abundance in the chinks of rocks and stone dykes often associated 

 with the Oak and Beech Ferns. It has a short, creeping rootstock, 

 but does not travel fast like its companions in question, but forms 

 its fronds in closer order. It needs moisture and shade. It may 

 be cultivated in same sort of soil and conditions as suit the de- 

 ciduous Polypodies, but is, unfortunately, extremely apt to turn 

 brown and become unsightly very early in the season, and hence 

 is not particularly to be recommended for culture. This remark 

 does not, however, apply to a constitutional variety, found in 

 Scotland and sent to the writer by the late Mr. R. Somerville, of 

 Edinburgh, which is not merely evergreen under glass, but is prac- 

 tically ever - growing, though otherwise normal, except, perhaps, 

 that it is of robuster growth ; vide sempervirens. Several varieties 

 are recorded, but we doubt very much whether the bulk of them 

 are in existence ; we, therefore, only mention the following : — 



Cristata (Fig. 140). — This variety was raised from spores 

 by Mr. C. Elworthy ; frond and most of the pinnae crested. 



The writer received a crested 

 form from Col. A. M. Jones 

 which is imputed to the sem- 

 pervirens or evergreen type, 

 scarcely, perhaps, justifiably, 

 though it is much more robust 

 '^SjffC^g!' than the normal, and remains 



^^Trr^T green much longer. It is 



^fesIl&IS? 7 peculiar in reverting sometimes 



to the uncrested type and then 

 returning even to grandiceps 

 forms. 



Dickieana (Plate XIII).— 

 Found in a cave near Aberdeen 

 by Dr. Dickie, and subsequently 

 in three other places in Scot- 

 land and Ireland ; very distinct 

 and far more beautiful than 

 the normal, the pinnae being 

 very broad and overlapping. 



Furcans. — Found in Scot- 

 land several times with all 

 fronds forked at the tips, and 

 occasionally the pinnae also. 



Fig. 140. C. f. cristata. SEMPERVIRENS. Found in 



