THE COMMON MATDENHAIR FERN 
ral, adherent to the rhizome, and as well as the rach 
with а few scattered 
Vernation circinata 
Fronds usually ovate or triangular, sometimes oblong or lanceolate, membranaceous, glabrous, 
netimes eighteen inches in length, bipinnate or tripinnate 
bright green, drooping, from six to twelv 
Pinna and Pinnules alternate, the latter of various forms: roundish with the base truncate 
sub-thomboidal, or obliquely fan-shaped, but generally more or less cuneate at the base, attached by 
ior lobate ; the sterile lobes dentate or 
inciso-dontate, the fertile obtuse or truncate, the sor often occupying their entire width. 
salar bundles 
Venation of the pinnules consisting of of dichotomous ramifications of the v 
of the petioles; the first fureation forming the extreme base of the pinnule, and the veins becoming 
gain and again forked in a flabellato-radiate manner, until the whole pinnule is traversed by a series o 
contiguous and therefore nearly parallel venules, which are disunited at their apices. In the sterile 
portions, one of these venules is directed to cach marginal tooth, in the apex of which it terminates, 
In the fertile portions, the venules extend to the margin, and are thence continued nearly across the 
indusium, there forming 
i oblong, more or less lengthened 
Fructifcation on the back of the fronds, generally distributed, 
according to the width of the lobe on which they are borne, seated on the under sur 
borne on the apices of all the lobes into which the anterior margin of the pinnules is divided. | Zndusium 
1 of the apex of the lobe, reflexed, and changed into 
of the same form, consisting, 
а thin bleached veiny membrane. Spore-eases globose. Spores roundish or angular, ovate, smooth, 
Рита nt, remaining until after young ones 
Tho rhizome is perennial, Tho fronds are persis 
are produced, if kept from being injured by frost. ‘The young growth commences in April and Мау 
The Adiantum is unlike every other British Fern; its black, shining, slender stipes, capillary 
ications, and fan-shaped pinnules, 
The M 
spoetive of its fructiiention, at once distinguish it 
mhair grows freely—in a moist close greenhouse, or in the stove, the temperature of which 
it enjoys—in the usual light compost of turfy peat and sand, with abundant drainage, "he rhizome 
14 not be buried in the soil, but fixed on the surface. The plants are injured by severe cold, even 
when in а closed house, so that it cannot be considered a hardy Fern. Pr 
fected by 
opagation is e 
division of the thi 
so widely over the world, it might be expected that modifications of form would occur 
and such indoed is the ease, two or three being met with even in this country. In addition to the usual 
state with lobed and decidedly wedge-shaped pinnules, we have, ther 
1. multifidum (УР). Dichotomous growth rarely occurs in this genus, but is occasional and inconstant 
2. incisum (М). This has both the barren and fertile pinnules deeply pinnatifid, or split down into 
long narrow lobes, but is otherwise of the usual growth. Marked examples aro rare in this country; one 
f 
ıd in Ireland by Dr, Allehin in 1853 is constant. Mr. Newman notices another from Mewstone Bay, 
in Devonshire. There are, however, various gradations of this structure, both native and foreign. 
3, rotundatum (М.ф). This sub-variety, found in the Isle of Man (a very similar one also on the south- 
d 
west coast of England) has at first sight a different aspect We have to thank Mr. Wilson 
Mr. Rylands for fronds from tho Mans locality, and several correspondents have furnished the analogous 
specimens from the English coasts, The chief peculiarity in the most marked, ie, the Manx plant 
consists in the basal pinnules having a rounder outline than usual, with the base truncate; the usual 
cuncated base, wanting in the 
pinnules, appearing, however, in the upper parts of the same fronds 
In addition, the fronds are narrow, and the pinna 
more spreading. We cannot, however, fix the limit 
of these peculiarities, intermediate and connecting specimens ocenrring from various localities 
