STRUCTURE. 1 5 
the species of temperate regions are best reared beneath a- 
hand-glass in a greenhouse ; and the tropical species 
should be placed in a hothouse. 
A convenient way of managing them is the following : 
Half-fill some shallow wide-moulhed pots with broken 
crocks, and on this put a layer of about two inches of 
turfy peat soil and mellow loam mixed with soft sand- 
stone broken in small Jumps of the size of peas; this 
compost should not be much consolidated. Next, shake 
or brush very gently over a sheet of white paper, a frond 
of the species to be propagated ; the fine brown dust thus 
liberated consists of the spores, in greater or less quantity, 
intermixed more or less with the spore cases. This dust 
is to be regularly and thinly scattered over the rough 
surface of the soil, which is immediately to be covered 
with a bell-glass, large enough to fit down close within 
the pot. The pots are at once to be set in feeders, and 
these are to be filled up with water ; they may either be 
placed under a hand-glass in a cold frame, or in a green- 
house or stove, as may be most proper. The first indica- 
tions of germination will consist in the appearance of 
little semi-transparent green scales. The supply of water 
must be kept up, and the glasses kept over the young 
plants. When two or three fronds are developed, the 
glasses should be tilted on one side for a short time every 
day, and ultimately entirely removed, the pots still being 
retained under a hand-glass. After a week or two they 
may be taken up, carefully separated, and potted singly 
in small pots. The young plants should still be kept 
under a hand-glass until established, and then gradually 
inured to the degree of exposure proper for the mature 
plants. Fern spores spring up in myriads on the surface 
of the soil, or on any undisturbed continually moist sur- 
face, about the growing plants, from which they are dis- 
persed as they ripen on the fronds. In hothouses this is 
so much the case that they sometimes become troublesome 
weeds. 
In their internal structure, ferns are the most highly 
