20 HAED FEEN. 



The radicles of this fern are black, tough and wiry ; the cau- 

 dex is tufted and hairy. The young fronds make their a^ipear- 

 ance in May : they are of two kinds, fertile and barren ; the 

 fertile fronds arrive at perfection in September, shed their seed, 

 and disappear before winter, but the barren fronds continue 

 perfectly green and vigorous throughout the year. The fertile 

 frond) represented of half the natural size in the figure at page 

 18) is erect, linear, simply pinnatifid, and pointed at the apex; 

 the lower half of the stem is dark purple, smooth, shining, and 

 naked, but furnished on each side with some minute rudimen- 

 tary pinnse, scarcely observable without a close inspection, and 

 having towards the base a few scattered, long, narrow, and 

 pointed scales: the upper half of the stem has linear, narrow 

 jpinnse, rounded at the apex, convolute at the sides, and densely 

 and completely covered with seed on the inferior surface. 



I have to acknowledge the obligations I am under to Miss 

 Beever, of Coniston, for fine Westmoreland specimens of this 

 plant, sparingly fruited, and to Mr. Jenner, of Lewes, for simi- 

 hxr Sussex specimens. From these I have been able to learn 

 more of the venation of this species than appeared possible from 

 an examination of the usual densely fruited form. In these 

 specimens the pinnules remain flat, as in the barren fronds, a 

 circumstance which much facilitates the inquiry. The mid- 

 vein of the pinna (a a a, page 21) is somewhat sinuous, giving 

 off obliqiie, alternate, lateral veins (b b h) ; these lateral veins 

 are united to each other by what may be termed an irregular 

 longitudinal vein (c c c), running parallel with the midvein, and 

 nearly equidistant between this and the margin of the pinna 

 {d d d) ; the union of the lateral veins causes the formation of 

 a series of what may be termed closed cells (e e e) : on each 

 side of the midvein, from the two longitudinal veins, arise other 

 lateral and slightly capitate veins (///), which proceed ob- 

 liquely towards the margin and terminate just before reaching 

 it ; to the two longitudinal veins are attached the capsules, in 

 a continuous series, on that side of each vein which faces the 

 midvein ; the points of their attachment are indicated in the 

 lower figm'e, throughout the course of the two longitudinal 



