PTERIS AQUILINA 219 
15 found. Its fronds (Fig. 255) are deep green, and erow to two ог 
three feet long from а caudex, 4 м Lady Fern, which, as we have 
said, it closely resembles, the chief difference being in the very small 
spore heaps, which, however, despite 
their resemblance to those of the Poly- (Ойг) Gh Si 
podium family, sometimes display a — ОЛ 
rudimentary cover or indusium, which | TN 
the true Polypody never does, and. [| 
what is more to the point, some of 
the recognized varieties of Lady Fern, 
the Horsfall plumosum to wit, have 
spore heaps of precisely similar nature. Despite its mountain 
habitats, where it grows among the rocks and is often in the 
clouds, it does quite well under culture, treated like the Lady Fern, 
and not allowed to get dry. Several varieties are recorded, viz. : 
FLEXILE (Plate XX XIII).—A narrow form with short pinne and 
more distant pinnules, deeply toothed, very distinct, found on the 
Cliva Mountains by Mr. Backhouse, and in Ben Lawers by Mr. 
Donald Haggart. 
LACINIATUM (Plate XX XIII).—A distinct form of flexile raised 
by Messrs. Stansfield; see illustration. 
CRISTATUM.—A thoroughbred, pretty cristatum found by Mr. 
Alex Cowan, of Penicuik, finely tasselled. 

Fig. 255. 2. alpestre (pinna). 
PTERIS AQUILINA (THE Common BRACKEN) 
(Plate XXXVI) 
The Common Bracken is probably the most widely spread species 
of Fern, since it is found nearly all over the world in more or less 
modified forms. In this country it covers large areas up to a 
level of about two thousand feet, monopolizing in many places 
` heaths, commons, and woodlands, and in the latter especially 
producing immense fronds eight or ten feet long, and, despite its 
commonness, of great beauty. Its botanical name means the 
eagle's wing. Fig. 262 shows a colony of a crested form of this 
species, and is peculiarly interesting as a rare example of a variety 
extending over a large area to the entire exclusion of the normal. 
The illustration shows that all the plants are tasselled, and Fig. 261 
shows the character to be well marked, and also depicts two other 
abnormal varieties found some fifty yards away on the same ground. 
In point of fact this Fern varies considerably, and given a fair 
acreage of it, we may be practically certain of finding three forms, 
the normal, a much leafier type, and a stiff, leathery, crispy form, 
much narrowed and of a darker green. The Pteris family, which 
is a very large one, has its spore capsules arranged in unbroken lines, 
immediately next the margin of the subdivisions, such margin 

