264 
Choice Ferns for Amateurs. 
NKl*liRODlUM—co7iUnued. 
cultivation is a compost of four parts of fibry peat and one 
part each of leaf-mould and sandy loam, with a free admix- 
ture of silver sand. N, montanum is one of the least variable 
of the British Ferns; but it has produced a few varieties. 
N. opacum. 
This garden name is applied to a plant having the 
appearianoe of la thick-leiaved, dull form of the popular N. 
erythrosorum, and staid, like thiat species, to be a native of 
Japan. Its fronds, however, never show, even in their 
young state, the beautiful tints whieh form the principal 
ornament of N. erythrosorum ; yet it is a most useful Fern, 
as its foliage is rarely affected by gas, smoke, or London fog. 
N. Otaria. 
In gardens, this Japanese species is better known as 
Lastrea aristata. Its robust fronds are produced from a 
thick, fleshy, underground rhizome, which delights in finding 
its way in any material of a rough or coarse nature — peat, 
partly-decayed vegetable matter, or even partly-decomposed 
moss; they are borne on stalks Gin. to 12in. long and of a 
scaly nature, and their leafy portion usually measures 1ft. 
or more in length. The terminal leaflet is 4in. to Gin. long, 
lin. to l^in. broad, and sharply pointed at its extremity, 
and it shows on both sides finely-toothed lobes reaching about 
a quarter of the way down to the midrib ; there are also from 
three to" six spreading, lateral leaflets on each side of the 
frond, the lower ones being distinctly stalked. The texture 
is leathery, and the colour a bright, shining green. This is 
a very ornamental and exceedingly useful plant, to which 
a certain character of distinctness is imparted by its large, 
conspicuous, closely-set sori, which cover nearly the whole 
under-side of the fronds. The plant known in commerce 
as Lastrea aristata variegata, though usually considered fis 
a form of this species, is undoubtedly a variety of Aspidiurn 
aristatum. 
N. patens. 
An extremely ornamental, greenhouse species, with a 
very extensive range of habitat. In North America it is 
called the Spreading Wood Fern. It is likewise found in 
Polynesia, Japan, Angola, tropical America, &c. The 
fronds vary according to the habitat, the largest of the 
North American species seldom being more than 2ft. in 
length and lOin. in breadth; they' are borne on roundish, 
pale green stalks, which also vary from a few inches to 
sometimes 1ft. in length, and which emerge from an oblique 
rootstock of a chaffy nature. The leaflets, 4in. to 9in. long 
and ^in. to fin. broad, are cut down about three-quarters 
