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containing a columella, closed by an operculum (or lid) and covered 
by a calyptra (or veil), but in Hepaticce the spores are produced in 
a blackish-coloured capsule which is without an operculum, and 
which opens to discharge the spores by valves, four to eight im 
number. Mosses have no elaters mixed with their spores, but 
plants of the order Hepatic have them and they are easily detected. 
They consist of two spiral fibres, which, so long as the spore case 
is entire, are closely coiled up but which, when free, stretch out 
like little corkscrews and aid in the dispersion of the spores. We 
must now turn Bryologists and give our attention to those most 
interesting plants which are the subject of this Kvenings Paper. 
Abounding in stagnant water, and in damp heaths, and entermg 
largely into the composition of peat are certain plants of a peculiar 
whitish or pinkish-white colour, and of such luxuriant growth as to 
form a beautiful soft carpet. These are sphagnums or Peat mosses 
of the order Sphagnacee. They take up a large quantity of water— 
which they retain a long time without rottmg—and are able except 
when young, almost to do without their roots. In the splitting of 
their capsules, they resemble Andrea a genus of mosses, and 
approach the Hepaticc:, but they differ from true mosses in their 
very peculiar leaf structure. The cells of the leaf are rhomboid or 
of irregular diamond shape, containing a spiral filament and 
appearing to be perforated here and there with holes. The 
Antheridia of Sphagnums being nearly spherical are unlike those 
of almost all other mosses while they resemble those of Hepatice. 
True mosses are called Urn-mosses because their capsule, with its 
separable lid, resembles an urn. And now, the way being so far 
clear, let us see what kind of plants we have to do with this evening. 
Let us ask first a few general questions and then go on to a closer 
examination of the various structures. What, then, are mosses ? 
They are cellular acrogens. And what are cellular acrogens ? 
Summit growers, made up, as already stated, entirely of that kind 
of tissue called cellular tissue. Mushrooms, lichens, and sea weeds 
are entirely cellular but are not summit growers—they are Thallo- 
gens. Ferns, Club-mosses, Pepperworts, and Horse-tails are 
summit growers but are not made up of cellular tissue only. On 
the contrary, they contain bundles of fibro-vascular tissue, and are 
called, on that account, Vascular Cryptogams. Have Mosses roots, 
stem, and leaves? Yes, these are usually well defined, so that our 
plants take higher rank than mushrooms, lichens, or seaweeds. 
What is to be said as to moss fructification? ‘This consists of 
microscopic spores, contained in the capsules already mentioned. 
Do the spores’ grow and produce new: plants? Notas a pea or 
bean does, but only indirectly. A pea or bean, the seed of a flower- 
ing plant, contains an embryo or rudimentary plant, but a spore is 
