234 



THE BOOK OF CHOICE FERNS. 



being no certain information of its occurrence either in China or India. In 

 North- West America it is widely dispersed, being found at Port Mulgrave, 

 Sitka and the Slave River ; thence through Columbia to Canada and the 

 United States on the one hand, and to California, Mexico, and Guatemala 

 on the other." 



The Common Polypody is so universally distributed throughout the 

 United Kingdom (where it is found growing naturally on walls, on roofs of 

 cottages, in hedges, on sandy banks, and particularly on old branches 



of trees), that it is unnecessary to give 

 here a list of its haunts. On account of 

 its importance, however, we cannot refrain 

 from quoting here a very instructive 

 extract from E. J. Lowe's excellent work, 

 "Our Native Ferns" (vol. i., p. 25), 

 which runs as follows : " From the habit 

 of this plant a character is added to the 

 landscape where it grows. A group of 

 pollard Willows clothed with Polypodium 

 vulgare are both singular and interesting. 

 The Matlock and Cromford Woods are 

 carpeted over with this species, the 

 rhizomes spreading along the rocks and 

 amongst the moss in the wildest profusion. In higher, more exposed, 

 and consequently more bleak situations, the form becomes compact and 

 the size considerably stunted. A very dwarf variety, scarcely differing 

 from the normal form, occurs along the raised banks of the hedges in 

 the salt districts about Northwich, especially near Wincham, and a similar 

 variety I noticed, subsequently, on Helvellyn and Fairfield, in the Lake 



District." 



Although the dimensions of the fronds of P. vulgare are greatly 

 influenced by the situation in which it grows, it may be stated generally that 

 they vary from 6in. to 12in. in length and from Sin. to 6in. in breadth, that 

 they are borne on firm, erect stalks 2in. to 4in. long, and that they are cut 

 down nearly or quite to the rachis into close, entire or slightly toothed, 

 usually blunt leaflets of a soft, papery, or sometimes stiffer texture and naked 



Fig. 66, Polypodium vulgare, showing (7) Habit and 

 (2) Portion of detached Frond 



(1, much reduced ; 2, i nat. size). 



