88 
APPENDIX. 
interstices of brick walls, such, for example, as Grammitis Ceterach, they will 
not flourish in brick rubbish. To treat this little-understood part of the subject 
intelligibly, and to show the extent to which the foregoing observation applies, it 
is advisable to divide the Ferns into various distinct sections, as follows : — 
STOVE AND GltEENHOUSE FERNS. 
Ferns with rhizomas. — These in their native habitats are, in many instances, 
epiphytes, deriving their nourishment chiefly from the air, or from other scanty 
sources. If potted they require much less water than others, the soil should be 
porous, and the pots should be filled half full of turfy peat. Most of this division 
thrive very well suspended on blocks of wood, in a warm moist atmosphere, but 
should be watered very sparingly in the winter season. The small, creeping, 
entire-leafed species thrive as epiphytes, as they run a long way in the season. 
These are readily increased by cuttings. If potted they seldom show any 
fructification, owing to their stunted habit. 
Ferns with crowns. — Those Ferns with crowns from which the fronds 
issue, require a soil made finer, with a greater depth. Care must be taken in not 
covering their crowns, which is certain death to the greater number of the species; 
they likewise require more frequent watering, as they are sooner affected by 
drought. Many of this section produce bulbs upon their leaves, from which they 
readily increase. Others root from the tip of their fronds, without forming bulbs; 
such is the case with many of the Aspleniums. This section requires care in 
dividing, as by this mode they seldom make good plants ; it is preferable to increase 
them from seed, as they grow more freely, and make finer plants. The Gymno- 
grammas should be potted in loam, as they are very apt to damp if potted in peat 
soil ; in fact, most Ferns which have various-coloured leaves prefer a loamy soil. 
No kind of manure should be at any time given to Ferns; even weak lime water 
should be avoided, as great havoc is sometimes made with it. 
Ferns with thick fleshy roots. — Of these there are but a few species. All 
those of Marattia have a curious scaly eormus, resembling that of the genus 
Zamia, from which are produced strong, thick, fleshy roots. They prefer loam 
and peat, and are easily injured by shifting, as the soil is very apt to chop from 
them when they are turned out of the pot. If kept too hot they are apt to drop 
their leaves ; they do best in a temperature not exceeding 60°. Danseas resemble 
the last genus, and require the same treatment. Care must be taken to give them 
free draining. 
Arborescent Ferns. — In general these do not thrive well ; they require a very 
moist atmosphere. Their stems should always be bound with Sphagnum, or they 
soon look very sickly, as they are covered all up their stem with spongioles, by 
which they, in a great degree, receive their nourishment. They should be well 
drained, and freely syringed on their stems to keep the moss moist. 
Numerous of the Ferns under stove culture are infested with a species of 
Thrips; others have a rusty appearance, often laid to that insect, but which 
appears to arise from being kept too warm — the greenhouse species, mixed with 
those properly belonging to the stove, being .always first attacked. Other insects 
seldom attack them, with the exception of brown scale and slugs, which are soon 
destroyed. The best remedy for the Thrips is the vapour arising from sulphur 
sprinkled over the flues or pipes. 
