(e) The prothalli.—Sow some bracken spores on damp earth and keep in a shaded place. Notice that the prothalli produced are very similar to those of the male-fern. Watch their development and the growth, on old prothalli, of a new generation of ferns. 3. The hart’s tongue fern.—Examine the hart’s tongue fern, and notice how it differs from the two previous types. Are the leaves simple or compound? Observe the brown trenches on the lower surface of the leaf. Try to get out some spores by running the point of a pencil along the trenches of a dried leaf. Sow the spores and try to raise prothalli. The daily life of a fern.—The everyday life of a fern is very similar to that of a flowering plant; for the organs by which it obtains food are—broadly speaking—of the same type. Ferns are lovers of damp and shady situations. The plant obtains its mineral food from the soil by means of its roots; and its spreading green leaves, or fronds, enable it, with the help of the sunlight, to decompose the carbon dioxide of the air and to build up starch, sugars, and other carbonaceous compounds. The male-fern.—The common male-fern (which, by the way, has no sex whatever) may be taken as a type of the group. It occurs abundantly in woods and hedgerows. The stem, or rhizome, is short and stumpy; it grows obliquely upwards, and does not branch. It is covered with old leaf-bases, which are clothed with brown, scaly hairs. The stem consists of a rather soft ground-substance, in which is embedded a hollow cylindrical network of conducting strands. In a cross section these appear as a somewhat irregular ring of dots (Fig. 146, 2, a). When the soft ground-tissue is carefully scraped away, the network of strands is left as a skeleton, with large diamond-shaped meshes. [Pg 186] The thin wiry roots spring from the bases of the leaf-stalks, just where these come off the stem. Fig. 146.—The Male-Fern. 1, Illustration showing general habit (× ¹ ₁₀); a, young leaves: 2, cross section of stem showing conducting bundles a: 3, portion of leaf; b, spore-boxes; a, covering scale: 4, longitudinal, and 5, cross section of group of spore-boxes; a, leaf; b, scale; c, spore-boxes: 6, a single spore-box; a, stalk; c, spring; d, spores.