








144 THE BRITISH FERNS. 
set of forms have the margins biserrate or lobato-serrate. Other 
forms are variously depauperated, giving rise to several very hand- 
some variations which are found to retain their peculiarities. Some 
forms are thin in texture, pale-coloured, and much divided, having a 
plumy appearance ; and not a few different forms are now known in 
which cristate tasselled terminal tufts are developed in different ways. 
The plant being evergreen, and extremely varied, may perhaps be 
entitled to rank as the most beautiful among our British species. 
1. angustifrons (M.). A very interesting form, remarkable on 
account of the narrowness of its dwarf attenuated fronds, which are 
in the specimens before us, about eight inches long, exclusive of the 
stipes, and barely more than an inch in width, the upper third 
being fertile. Fronds narrow linear-lanceolate, attenuated at the 
apex, distinctly bipinnate; the pinnules are small, close-set, normal 
in character, bristly-serrate, and auricled: about three pairs on the 
larger pinne being stalked, the rest confluent. It was found at 
Barnstaple, Devonshire, by Mr. Jackson. Mr. Clapham reports it 
to be sometimes cornute. 
We have another small and narrow fertile form of this species 
apparently differing from angustifrons, provisionally named steno- 
phyllum. The fronds are nearly nine inches long, and almost two 
inches across the middle, the upper part being attenuated ; they are 
bipinnate, the lower pinnules distant, the basal pair only stalked 
and auricled, and the rest confluent with a rounded anterior 
margin, in this respect closely resembling P. aculeatum, v. lobatum. 
It was gathered by Mr. Wollaston, in Devonshire. 
2. hastulatum (M.). This is a small pinnuled form, quite like the 
Italian hastulatum of Tenore, as figured in the Flora Napolitana. 
It is chiefly remarkable for the small size of the acute pinnules, and 
for their distinct and slender footstalk ; the auricle, too, is very dis- 
tinct, acute, and in the case of the lower pinnules is separated by a 
deep incision from the rest of the pinnule. It has been found in— 
Surrey : St. Martha's Hill, near Guildford. Devonshire, Rev. J. 
M. Chanter. [Plate XIX D.—Folio ed. t. XII B.] 
8. quadratum (M.). A remarkably neat small-pinnuled form, the 
chief peculiarity of which is the approach to squareness in the 

