Hitherto we have dealt only with flowering plants. In these sexual organs are borne in more or less conspicuous blossoms, and, as the result of fertilization of the ovules by the pollen, seeds are produced which give rise to plants exactly like that which bore them. Ferns produce an enormous number of minute bodies, called spores, which are incapable of developing directly into a plant similar to that by which they were produced; but on germination they give rise to a minute green scale, like a liverwort, upon the under surface of which sexual organs appear, and by the mingling of their cell-contents a true bud is formed, from which a true fern-plant is evolved. There are other important points upon which ferns differ from flowering plants, but it is not within the author’s province to deal with them here. Let it suffice to add that as a fruit-bearing organ the leafy portion of a fern differs greatly from the leaves of other plants. To prevent confusion it is termed a frond.

The Hart’s-tongue has a frond of very simple character—strap-shaped—consisting of a stout mid-rib (rachis), with a leathery green expansion on either side, the upper end tapering off to a point, the lower divided into two lobes. A large number of thick red-brown parallel ridges on the under surface will attract immediate attention. These are heaps of delicate capsules (sporangia), which contain the spores. The Hart’s-tongue is a plant of sandy or rocky hedgerows.