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containing a columella, closed by an operculum (or lid) and covered 

 by a calyptra (or veil), but in Hepaticoe 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 in 

 number. Mosses have no elaters mixed with tlieir spores, bufc 

 plants of the order Hepaticoe 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 

 lilie little corkscrews and aid in the dispersion of tlie spores. We 

 must now tm-n Bryologists and give our attention to those most 

 interesting plants which are the subject of this Evenings Paper. 

 Abounding in stagnant water, and in damp heaths, and entering 

 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 S2)hagnaceoe. They take up a large quantity of water — 

 which they retain a long time without rotting — and are able except 

 when young, almost to do without their roots. In the splitting of 

 their capsules, they resemble Androea a genus of mosses, and 

 approach the Hepaticoe, 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 Hepaticoe. 

 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 Avhat 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 acrofjens. 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 grovv'ers — they are Thallo- 

 gens. Ferns, Club-mosses, Pepperworts, and Horse-tails are 

 summit giowers 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 '? Not as 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 



