A Dictionary of Choice Ferns. 
127 
they produce fronds of a hardier and more substan- 
tial texture, it is under the combined influences of 
shade and moisture that their most vigorous growth 
is produced; they should therefore be sufficiently 
shaded to prevent the sun from burning the fronds 
as they unfold, as also to keep them from being dis- 
coloured when fully developed. Like all other Tree 
Ferns, very little pot-room suffices. They should be 
potted, tubbed, or, better still, planted out in the 
houses, in a compost of three parts of peat, one part 
of fibrous loam, and one part of sand as coarse as 
procurable; in this they will grow luxuriantly for 
years without requiring further attention than con-, 
stant moistening. A. excelsa is grown in large 
quantities for market. It is also a useful species for 
sub-tropical gardening. 
A, Van Geertii, and perhaps a few other species, 
produce young growths on their stems, from which 
they can be propagated ; but generally speaking, 
Alsophilas are increased from spores, which are 
abundantly produced and germinate freely under 
warm treatment. 
A. aspera. 
A very handsome, stove species, also known as A. nitens, 
native of the West Indies, and readily identified through the 
large, glossy^ spear-shaped scales, lin. or more in length, 
found at the base of the stalks. The trunk is 10ft. to 30ft. 
high, slender, and covered with short, stout spines, which 
also extend to the stalk and to the rachis or stalk of the 
leafy portion of the fronds. These fronds, which reach 
some 10ft. to 12ft. in length and are gracefully arched 
(Fig. 64) and of a very light and pleasinc^ green colour, are 
hipinnate. The oblong leafits are borne on short footstalks ; 
they are cut down from half to two-thirds of the way to their 
midrib ; their lobes are oblong-egg-shaped, often sharply 
toothed, and their midrib shows on the under-surface some 
blister-like scales. The sori of a very deciduous nature, are 
situated half-way between the midrib and the margin of the 
fertile pinnules. 
A. atrovirens. 
South Brazil is the home of this gigantic species. Its 
large tripinnatifid fronds are borne on stalks about equal 
in length to their leafy portion, stout and slightly 
scaly. Their rachis, of a dark straw-colour, sometimes 
