24 CULTURE. 
pagation must be attempted, is to destroy, by some gentle 
process, the axis or extreme point of growth, to wait pa- 
tiently until the lateral crowns which may thus be forced 
to develop themselves, have gained some strength, and 
then to divide as before ; only, in this case, very much 
more care is necessary in the process of division. The 
spring season, just before growth recommences, is the best 
time for these operations. 
The most interesting mode of propagation, however, is 
by the spores. The mode of raising these described at p. 15, 
may serve for the mere purpose of propagation. Where, 
however, exactness in the results is an object, or where it 
is desired to watch the progress of development, either 
in a cursory way, or more minutely by means of a micro- 
scope, other methods will be found more convenient, and I 
know of none which can be more strongly recommended 
than that which has been described in Mr. Ward's valuable 
book, " On the Growth of Plants in Close-glazed Cases," 
by Mr. Deane, of Clapham, in a letter the substance of 
which I will transcribe : 
Mr. Deane's intention was to procure some soft porous 
potter's ware material, that should readily imbibe and re- 
tain moisture, upon which to sow the spores. He, how- 
ever, met with a peculiarly fine and soft sandstone, which 
was equally adapted to the purpose, and with this his 
experiments were made. The stone was prepared by 
breaking it into pieces of from one to two inches square, 
and less than one inch thick, the faces being rendered 
parallel and smooth by rubbing on a flat stone. The ob- 
ject of thus adjusting the size and smoothness of the pieces 
of stone, was to facilitate their being placed for observa- 
tion on the stage of a microscope. Before sowing the 
spores, the prepared pieces of stone were baked in an oven 
to destroy any organic matters which might be lurking 
about them. They were then moistened with distilled 
water, and covered with bell-glasses, preparatory to re- 
ceiving the spores. The spores were obtained by laying 
recently-gathered fronds with mature fructification be- 
