246 THE BOOK OF CHOICE FERNS. 



is carried far enough, frequently form wide crests of a peculiarly flat nature. 

 — Lowe, Our Native Ferns, i., fig. 29. Moore, Nature-printed British Ferns. 

 Druery, Choice British Ferns, p. 122. 



P. Y. semilacerum — se-mil-ac'-er-um (half- torn), Link. 



This is the P. v. hihernicum, or " Irish Polypody," of Moore, and the 

 most compound of all the permanent fertile forms of the species known in 

 cultivation. It is also called the " Dargle Fern," having originally been 

 found near the Dargle Valley, Wicklow, where the fronds are well marked, 

 and at Killarney. Its habitat is not, however, limited to Ireland, for Lowe 

 states that it has also been found in a wild state in Devonshire, Norfolk, 

 Kent, Monmouth, and Carnarvonshire, as well as on the Carberry Island 

 in Lough Eee, near Athlone. Though not characteristic until it has attained 

 a good size, this is an exceedingly handsome Fern, and quite constant under 

 cultivation. Its long-stalked and nearly upright fronds, 1ft. to IJft. in 

 length and 6in. in breadth, are very deeply bipinnatifid in their lower part, 

 and become fertile and pinnatifid towards their summit, the fructification 

 being bold and prominent. The under- side of the frond is of a pale green 

 or somewhat glaucous colour, and the leafits, or lobes, are narrow, sharp- 

 pointed, and saw-toothed. — Lowe, Our Native Ferns, i., t. 8. Moore, Nature- 

 printed British Ferns. Nicholson, Dictionary of Gardening, iii., p. 195. 



P. Y. serratum — ser-ra'-tum (saw-toothed), Moore. 



In the most typical state of this form, which is somewhat variable, the 

 leaflets are deeply serrated. The fronds are large — more than 1ft. long and 

 from 4in. to 6in. broad. When well grown it approaches P. v. semilacerum 

 in form, and sometimes, having rounded, enlarged teeth, it also approaches 

 P. V. crenatum. This variety has been found in Guernsey, at Milnthorpe, 

 Conway, Fountains Abbey, Byland Abbey, Bowness, Lancaster, in Westmore- 

 land, &c. — Lowe, Our Native Ferns, i., fig. 30. Moore, Nature-printed 

 British Ferns. 



P. Y. serrulato-bifidum — ser-rul-a'-to-bif -id-um (small-toothed and 

 forked), Monkman. 

 This handsome form, originally found at High Hutton, near Malton, 

 is, like most of the bifid forms, somewhat inconstant in cultivation. Its long, 



