sisa 
ON THE GERMINATION OF CLUB-MOSSES. 
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flowering plants, effecting a fertilization of a germ produced by the large spore. The changes which 
these small spores themselves undergo are as follows:—At a variable, but often a long period after 
they are sown, the coat bursts, and a delicate inner coat protrudes a little ; this also becomes ruptured, 
and from it emerge very minute cellular vesicles which have been produced in its interior, and each of 
these bursts to allow the exit of one of those mysterious, actively moving, spiral filaments, such as we 
find in the “ antheridia” of the other Cryptogamous plants. According to M. Hofmeister, these bodies 
are not set free until more than five months after the spores are sown, in Selaginella Helvetica. 
The other kind of spores is very much larger than the “ pollinic” spore, and is the true reproductive 
body, analogous to the ovule of flowering plants. The changes which it exhibits are very remarkable, 
and it requires very minute microscopic dissection to trace them. At the time these large spores are 
shed from the sporangium, an exceedingly delicate layer of cellular tissue is found inside the thick 
coat, at the upper end. This layer of cells is analogous to the delicate little green leafy body produced 
by the Fern spore when it germinates; but here it is formed inside the spore. After a time we may 
discover upon it structures closely resembling the “ pistillidia” or “ archegonia” of the other 
Cryptogamous plants, and when these have become perfect the outer coat of the spore cracks just over 
them and folds back in triangular flaps so as to lay them bare. It is supposed that fertilization now 
takes place by one of the spiral filaments coming in contact with the germ-cell contained in an 
“ archegonum.” At all events, the germ-cell of one of the “ archegonia” is soon after found enlarging 
and dividing into several cells, and growing down into the centre of the spore. Here the embryo 
enlarges still more, and gradually acquires form, exhibiting a leaf-bud and a nascent rootlet, which, 
by their increasing size, burst the spore and make their way out, in which stage they may be recognized 
by the naked eye as closely resembling in appearance a little Dicotyledonous plant, springing from 
its seed ; having a descending, thread-like root, and a slender stalk bearing two little leaves with a bud 
between them. 
Through the kindness of Mr. Moore, I had an opportunity of verifying much of the above in some 
spores of Selaginella denticulata and S. stolonifera, which germinated in one of the houses at the 
Chelsea gardens, in the beginning of the past winter. I found the structures described in the large 
spores, and traced the gradual development of the young plants from them; but I only found the 
burst empty coats of small spores, not having hit upon any in a sufficiently early stage. A curious 
fact connected with this is related by M. Hofmeister; as already stated, the spores are often a long 
time germinating, but the large and small ones differ in their periods ; thus the small spores of S . 
Helvetica produced their spiral filaments in about five months, while the large spores, sown at the same 
time, did not exhibit “ archegonia” until six weeks later. And all experiments of sowing both kinds 
» 
of spores together, or large spores alone, were fruitless; the only way in which the large spores could 
be made to germinate, was by keeping a living and freely fruiting plant growing under the glass 
shade in the pot in which the spores were sown. As the small spores ripen gradually from the bottom 
to the top of the spike, a succession of them is thus afforded, some of which produced their filaments 
at the exact time required. The spores of Selaginella Martinsii , and other tropical species germinated 
in a few weeks after sowing. These points should be attended to by those who cultivate these plants. 
They indicate also a possibility of obtaining hybrids by sowing the large spores in pots containing 
growing plants of other species, isolated by being covered with a bell-glass. 
The species of Lycopodium proper, to which our indigenous L. clavatum, inundatum , &c., belong, 
only produce one kind of spore, and these small. M. Hofmeister states, that he has not succeeded, 
after repeated trials, in causing any of them to germinate. He considers it probable that they produce 
a “ prothallium” (that is, the cellular structure found inside the large spore) on which, as on the ger¬ 
minating Fern, both “antheridia” and “archegonia” are produced, consequently that they are 
androgynous instead of monoecious.— Arthur Henfrey, F.L.S. 
