120 PLANT PROPAGATION 
Ferns differ from the seeds of flowering plants, inas-- 
much as the latter have already been fertilised, and 
each perfect seed contains an embryo bud or plant in 
miniature. Spores, on the other hand, are simple cells 
of protoplasm endowed with life, fertilisation being 
effected when the growth therefrom reaches the pro- 
thallium stage. Any time during February or March is 
a good time to sow the spores of Ferns. By doing so 
at such an early season the young plants are enabled to 
attain sufficient size and strength to pass through the 
following winter with safety. It often happens that 
when the sowing is delayed until late in the season the 
young plants lack the strength to withstand the foggy 
and prolonged dull weather to which they are subjected. 
Pots 5 inches in diameter are a suitable size to use, and 
they should contain drainage material (broken potsherds) 
to two-thirds of their depth. The soil when pressed 
down should reach to within 4 inch of the rim, and may 
consist of a mixture of peat and loam that has been 
passed through a sieve of 4-inch mesh. Before use it 
should be either scalded or baked sufficiently to destroy 
all weed seeds and germs it may contain. A thorough 
soaking of water should then be given, and a short time 
allowed for it to drain. The spores, which are extremely 
minute, should then be thinly scattered all over the 
surface as evenly as possible; they do not need any 
covering with soil. A sheet of glass should be placed 
on the top of each pot for protection, and also to retain 
moisture. The soil must be kept continually and 
uniformly moist; but on no account must any attempt 
be made to water over the surface, or the spores will 
inevitably be washed away. The pots should be stood 
in saucers of water in a shady but light part of a frame 
