THE POLYSTICHUMS 217 
WAKELEYANUM (cRUCIATUM).—Found in S. Devon by Mrs. 
Wakeley ; pinnze set on in pairs at right-angles, forming crosses with 
opposite pairs; one of the parents of Mr. E. J. Lowe's hybridum 
aculeatum. 
Рогузисном LONCHITIS (THE HoLLy FERN) 
(Plate XXXII) 
This Fern has been named the Holly Fern, owing to the hard, 
leathery texture of its fronds, and the shape and prickly edges of 
the pinne or subdivisions. It is purely a mountain Fern, and in 
Great Britain is never found wild at а lower elevation than IIOO 
feet, most of its habitats being far above that limit, 2000 to! 3000 
feet. It grows in the chinks of the weathered rocks, or in the short 
grass or other growths under their lee. At the ттоо level, near 
Aberfeldy, we found numerous large plants in rocky soil among the 
heather, where, at a distance, the projecting, erect fronds were at 
first taken for the fertile fronds of the Hard Fern (Blechnum spicant), 
and, but for the guidance of the Rev. Mr. Maclean, of Aberfeldy, 
who had previously discovered the station, we should certainly have 
overlooked it, since it occurred on level ground, close to the road. 
It has been found in England, Scotland, Wales, and Ireland, where 
mountains of sufficient elevation have encouraged the search. 
It is distinguished from the other two species by being persistently 
only pinnate, that is the pinnae are never divided to the midrib, 
ч see Fig. 253. Reported finds of the Holly 
сс ОЛОО Fern at lower levels are not infrequent, 
| 
N but are invariably found to be young 


IT, qu forms of P. aculeatum, by the fact that 
N | 2 apart from their less rigidity, the lower- 
==. QUEE. : : з M 
N ТІП) most pinne are invariably divided. Тһе 
чу S separation of the species from P. aculea- 
Al) / tum is entirely justified ; it is not merely 
== a mountain form of that, compressed 
and dwarfed by exposure to hardening 
influences, and when the spores are sown, 
the parent form is truly reproduced. Furthermore, plants collected 
and brought down to lower levels do not respond to milder conditions 
by larger growth, or the assumption of aculeatum characters, but are 
difficult to grow, requiring pure air and cooler conditions. We have, 
however, seen very decent specimens in the open where fairly 
congenial conditions exist, say in rockeries with stony soil, con- 
stituting a fair approach to their natural environment. The 
different pressure of the air is by some considered as constituting 
Fig. 253. P. lonchitis. 
a difficulty, but we hardly share this view. We have expressed the ` 
opinion that the species is justifiably set apart from P. aculeatum, 
but may mention that several peculiar cases of the latter species 
have mysteriously appeared among sowings of P. lonchitis, to- 

