Select a plant bearing a ripe capsule, and warm it gently before the fire—holding it over a sheet of paper—to dry it. Examine the mouth of the capsule with a lens, and try to see the teeth which surround the opening. Then shake the capsule over moist soil in a small flower-pot to scatter the spores; cover with a sheet of glass and keep in a warm room. In a few days notice that the soil is covered with fine green threads. Ultimately new moss plants will grow from these. The life-history of a liverwort.—One of the commonest and simplest of this class of plants is known to botanists as Pellia. It may generally be found growing by the sides of streams or old wells. It has neither stem, leaves, nor root, but consists of flat, green, overlapping lobes which fork at their ends. It branches very freely, and in spring the new branches give the ends of the lobes a frilled appearance. A rather prominent midrib runs along each branch. The plant is attached to the soil by a large number of fine hairs which spring from the lower surface of the midrib. The whole appearance of this liverwort is very suggestive of the prothallus (Fig. 147) of a fern; and, indeed, it corresponds to a prothallus, not only in its general structure and mode of life, but also in bearing sexual organs of a very similar type. It was seen in Chapter X. that a fern prothallus at length produces an embryo, which grows up and forms the spore-bearing generation which is what people usually understand by a “fern”. Fig. 156.—A Moss. A, a plant with spore-case still covered by hood (c) (× 1). B, a plant with ripe spore-case (k); s, stalk; d, lid; rh, hairs (× 1). C, mature spore-case with lid (d) removed; p, fringe of teeth (× 3). The liverwort also gives rise to a spore-bearing generation, but in [Pg 201] this case it consists merely of a small, round, spore-box, dark-green in colour, which is carried on the summit of a white stalk—the whole looking somewhat like a stout pin. In February, or early March, the spore-boxes may be seen upon the upper surface of the plant as small balls, perhaps one-sixteenth of an inch in diameter, protruding from the mouth of a little pocket in which their early stages are passed. About May, their stalks lengthen so rapidly that in a few days the spore-boxes are lifted to a height of two or three inches. Then each box opens by its wall splitting into four, and the spores are liberated to germinate and form new liverworts. Having thus shed the spores, the box and stalk die down.