THE BLACK MAIDENHAIR SPLEENWORT 
A very fino example before us, the leafy part is eight inches d, the stipes nine inches 
They are quite smooth, and in outline are sometimes deltoid, or perhaps more correctly 
pentangular, the apices of the lowest posterior pinnules forming additional angles ; sometimes ovate 
with the point much attenuated, Full-sized examples of the latter, and a rather small frond of 
the former state, are shown in our Plate, The smaller might be supposed to indicate a le 
unt of the 
dition of the plant, but we are scareely prepared this explanation, on 
ceeurrence of equally. small fronds in which the pentangular outline is preserved, while again the 
ovate fronds are often abundantly fertile; and we would rather suggest that it is an instance of that 
profusion of form in Nature which mocks at our specific definitions, In the larger fronds, which are 
most quadripinnate, the pinnas, especially the lowest which is also the largest, are of the same 
subdeltoid outline as the frond itself, excepting that as the pinnules are alternate and not opp 
the lower pair of pinnae are, | 
gree of obliquity almost producing a trapeziform outline 
The apices of the pinnas as well ules, are caudate, with a few 
f the frond, and generally of the p 
the 
mewhat obliquely ovate 
attenuate, and their divisi nte 
mdary pinmules, are lanceolate, deeply pinnatifid at a very a 
wer of which aro about three-toothed, the upper bifid at their points, 
narrow and very acute 
these lobes as well as the simple teeth at the apex of the pinnule itself being 
"The pinnae towards the apex of the frond, and the pinnules towards the apices of the pinne, become 
gradually narrower than the basal ones ove, until they both become reduced to linear 
lanceolate sharply toothed lobes, and these gradually merge into the simple linear teeth of the 
caudate extremities. А similar mode of division, but on a smaller scale, obtains in the smaller forms, 
The 
ing only tripinnate, and the secondary pinnules narrower, and less deeply lobe 
veins, though slender, are very distinct ; they consist of а series of furcations, that is to say, the vein 
which re 
pr 
former simpl 
sents the midvein of the pinnules forks below each of the lobes or teeth, and the venule thus 
› 
duced proceeds along the tooth or lobe until it nearly reaches the 
apex, being in the case of the 
and in the ease of the latter again forked o 
r twice, according as there may be tw 
three apical teeth, No one who has ob wainted with our 
хуей the venation in this plant, and is ac 
British Asplenica, can fail to notice the similarity in form and division and in the condition of the 
veins that exists between some of the pinnules of this plant, 
specially the shorter and broader ones of 
the less divided fronds, and some fronds of 4. septentrionale. There is no definite midvein, but a series 
f fureations only, so that this plant alone furnishes sufficient evidence against the adoption of 
Mr. Newman's group Amesium as а genus, The sori are very narrow, linear, borne, as in A, Adiantum- 
nigrum, contiguous to each other, and near the centro of the pinnules. The indusium is white, semi- 
t is one of unusual elegance, both on account of its minute sub- 
Some other variat 
ms of this species deserving of record, are included in the following summary 
1. obtusum (ҮШІ). This fo 
already described, is rarely more than bipinnate, though sometimes 
tripinnate, with roundish or bluntly ovate pinnules, not. very e 
nspicuously toothed. It is less defined. 
than some other forms, some of the smaller states 
ion plant approaching it very closely, but 
as it occurs under different phases, it seems to claim recognition at least as a variety of se 
importance. A tripinnate exa 
of this form has been communicated by Mr. D. М m the 
county Antrim, Ireland. 
2. oblongum (N). The chief peculiarity of this form is the parallelism of the sides of its fronds 
Which thus become marrow oblon 
like what occurs in Lastrea spinulosa; the pinnw are short 
remarkably triangular, acuminate, the three lower pairs almost equal in size. "ho subdivisions are 
small; otherwise the structure is normal, We have received it from Mr, Jackson, of Guernsey, and it 
lso been found by Dr. Allehin. 
