ASPLENIUM. 21 
XASPLE'NIUM ADIA'NTUM-NI'GRUM. 
THIS, the Black Maiden-liair-like Spleenwort, is popu- 
larly known as the Black Maiden-hair, and Oak Fern. 
Its main root is black, scaly, and furnished with many 
wiry, dark-coloured rootlets. The fronds rise from the 
crown of the root, and vary in height from three inches 
to nearly two feet. The specimen fronds from which 
our drawiug was taken, and which is about one-third 
the natural size, were about fifteen inches high. These 
greater heights are attained by the Fern when growing 
in a shady situation and rich soil, as was our specimen 
at Sherfield, in Hampshire. The stem of the frond is 
dark chesnut-coloured, and glossy; the part joining the 
root scaly; about half of its length bare, and the other 
half leafy. The leafy portion has a lengthened - tri- 
angular form, the lower pair of the leaflets being 
longest, each pair above them being gradually shorter 
and shorter, until they pass insensibly into the single 
terminating leaflet. The leaflets are also lengthened, 
triangular in form, and are more or less alternate, and 
so are the leafits composing each leaflet. The leafits 
are spear- head-shaped, and so finely toothed at their 
edge as almost to appear fringed. The pair of leafits 
nearest the main stalk of the frond are so deeply cut as 
to be divided into still smaller, or sub-leafits. They all 
are bright light green on the upper surface, but the 
under surface is much paler. 
The fructification (sori) appears at first in oblique 
