336 Observations on the Germination of Ferns. 
this should be repeated whenever the surface of the pot begins to 
get dry, particular care being taken to sprinkle the water evenly, and 
not to inundate the pot : a little should be given at a time, allow- 
ing it to be absorbed by the soil before it is repeated, and if possi- 
ble it would be better to use only rain water. 
In sowing the seed, if it has been recently gathered, it will be 
necessary to avoid sowing too much, a very small quantity will suf- 
fice to sow a pot, merely a thin dusting spread regularly over the 
surface. As the seed is extremely minute, the error of sowing too 
much is more easily committed than avoided, but it should be guard- 
ed against, as the seedlings are more likely to succeed if only a mo- 
derate crop, than when thickly crowded ; the seeds of ferns, how- 
ever, like the seeds of other plants, are apt to lose their vegetating 
qualities with age, and if the seed has been gathered a year or two, 
it will be necessary to sow it thicker. 
Due attention must be paid to the state of moisture on the sur- 
face of the mould, after the seeds are sown, to guard against such 
an excess of it as will cause mould or any minute algae to grow, keep- 
ing just such a state of humidity as will supply the absorbent wants 
of the seedlings. 
As soon as the lobes of the seedlings begin to widen and assume 
a determinate shape, the hand-glass may be tilted up, and a little 
air admitted, and this may be increased from time to time until the 
plants can bear exposure ; if they are too much crowded, they may 
be successfully thinned out, and the thinnings transferred to another 
pot : and it must be observed that the glasses should he shaded du- 
ring very bright sunny weather, or placed under the shade of other 
plants. 
These directions will sufficiently enable any one to repeat the ob- 
servations on the germination and primary vegetation of ferns to 
which the following remarks refer. The sporules of the different 
sorts of ferns vary much in the time they take to germinate after 
they have been committed to the earth ; some will appear in eight 
or ten days, while others will not be discernible in less than a 
month. In consequence of their extreme minuteness it will require 
a high magnifying power to enable any one to observe them during 
that process. 
The first trace of germination is indicated by the appearance of 
a number of exceedingly minute green specks on the surface of the 
mould ; if one of these is placed under a microscope it will be found 
that the sporule has burst open into two nearly equal halves, arid a 
small greenish body occupies the lacerated orifice. This is, as far 
3 
