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THE FRUCTIFICATION OF LICHENS, AND OTHER CRYPTOGAMS. 
79 
transferred to a portion of a new cold pit, kept close for a few days, and then gradually hardened so 
as to bear full exposure, and they were only protected from heavy dashing rains. By the beginning 
of October they were dormant, and looked very strong and healthy. It. Aucklandii had grown to 
nearly a foot, It. Dalhousice and It. argenteum six inches, It. niveurn and It. Falconerii to about three 
inches, with large woolly reticulated handsome foliage; the rest averaged from one to three inches. 
It. ciliatum is a perfect gem as to foliage, which is close, compact, dark green, and looks as hardy as a 
Ponticum. It. Fdgworthii is another very distinct foliage, so also is It. campylocarpum ; indeed, they 
all promise to introduce a new feature in the way of foliage. When dormant, I wedged in some damp 
moss very tightly into all the interstices between the pots, in which state they remain, and are now, 
with the exception of four, started into a strong and healthy growth; I give them a constant circula¬ 
tion of air, and very often full exposure, and do not intend to let them have any artificial heat again. 
I am quite aware that by hard forcing there may be much larger plants, but will they stand as fair a 
chance when submitted to all the vicissitudes of our weather, which the greater portion of them 
must eventually come to ? I think not.— John Cox, Redleaf. 
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THE FETTCTIFICATION OE LICHENS, AND OTHEE CEYPTOGAMS. 
I7HHE development of the fructification of Lichens has been lately brought under the notice of the 
A Botanical Society of Edinburgh, by Wyville T. C. Thomson, Esq., who defines the spores as being 
ultimate germinating cellules, the product of the division of the compound granular cell which is the 
result of the union of the conjugating cells in cryptogamous plants; sporidia as compound granular 
cells, the product pf the union of conjugating cells; proto-sporidia as the simple cells of Lichens, in 
which the two conjugating cells are afterwards formed ; gonidici as free cellules, derived from, and part 
of, the cellular tissue of the parent plant, capable of continuing, to a certain extent, their development 
when free from the parent, without the intervention of the true generative act of conjugation (the 
analogues of free buds or bulbils in flowering plants) ; and th e pro-embryo in Ferns and other Crypto¬ 
gams as the cellular expansion formed by the development of the gonidium, and containing the con¬ 
jugating cells. This pro-embryo, then, corresponds to the ordinary cellular expansion of Lichens. 
The fronds of Lecanora tartarea , a crustaceous Lichen, holding a middle place between the foliaceous 
and the pulverulent species, show first a mass of elongated, more or less filiform cells, mostly empty, 
delicate, and of a light grey colour; and resting immediately above these are groups of rounded cells 
filled with bright-coloured chlorophyll, scattered in small irregular patches, or as isolated cells among 
the grey tissue. Above the green cells is another layer of transparent tissue, closely resembling that 
below it. In lecanora we have, above all, a layer of somewhat flatter cells, forming an imperfect 
epidermal covering. The green tissue appears to represent the living and actively vegetating part of 
the Lichen determining by its development the form of the frond, and giving origin to all the other 
tissues. The green cells termed gonidia frequently accumulate in masses, burst through the cuticular 
layer, and appear as a green powder on the surface of the plant. In this state the single gonidia are 
capable of continuing the powers of cell development at a distance from the parent, forming round 
themselves the grey hygrometric tissue; and, like the parent plant, producing at length true reproduc¬ 
tive organs. This is by no means a solitary instance of the formation of these from developing cells 
in the vegetable kingdom. We have in the Ferns an instance of another order propagating through 
gonidia. In the Ferns, cells, long called spores, are found within modified leaves, or parts of leaves. 
These cells, when placed in favourable circumstances of heat and moisture, develop, by nuclear division, 
a small cellular expansion (still part of the parent plant, as no process of cell conjugation has inter¬ 
vened), called the pro-embryo. On this pro-embryo two cellules, of different character, appear; an 
union takes place between the different cells, and the product is an ovoid body, the sporidium. Within 
this sporidium by nuclear division, spores are produced, only one of which comes to perfection, the 
