poisonous, or at least questionable properties. The L. catharticum has been administered as a strong cathartic. In the Highlands they are employed with alum to fix the native dyes in the manufacture of tartan, while they are said themselves to produce a blue tint.

Lycopods may be said to present the highest type of cryptogamic vegetation, the highest limit capable of being reached by flowerless plants. Indeed, they are said by botanists of the highest reputation to bear a close affinity to coniferous trees, to be, in fact, pine-trees in miniature. This affinity though indicated by very curious resemblances is, however, strictly analogical. The gap between the two great orders of plants is too wide to be overleaped by a sudden transition. There is a resemblance in external form, habit, and fructification; the leaves are in both cases linear; the seeds are in both cases produced from cones or spikes; the formation of the archegonia and embryonic pods of the one, is similar to that of the corpuscles and embryo in the other, but in these points the likeness begins and ends. There is no true homology, but a mere analogy which is often seen to harmonize the most dissimilar works of nature, as if to show that they proceeded from the same creating hand. There may be gradual transition from one class of plants to another, and certain characters may be common to two families; but still there are definite groups in nature, and typical characters belonging to plants, which will for ever keep them distinct and isolated, as illustrations of the infinite variety of the Divine works.

The first pages of the earth's history reveal to us very

extraordinary facts with relation to members and allies of the moss tribe. The club-mosses, in particular, at a former period seem to have played a more important part, or to have found conditions more suitable to their luxuriant development than is the case at the present day. Some of them are stated to have formed lofty trees eighty feet high, with a proportionate diameter of trunk. They are the most ancient of all plants. The oldest landplant yet known is supposed to be a species of lycopodium closely resembling the common species of our moors.

In

the upper beds of the Upper Silurian rocks, they are the only terrestrial plants yet found. In the lower Old Red Sandstone they also abounded; while they occupied a considerable space in the Oolitic vegetation. But it is

in the Coal-measures that they seem to have attained their utmost size and luxuriance, sigillaria, stigmaria, lepidodendron, etc., being now considered by competent botanists to be highly-developed lycopodia. Along with ferns, they covered the whole earth from Melville Island in the Arctic regions to the Ultima Thule of the Southern Ocean, with rank majestic forests of a uniform dull green hue. The numerous coal-seams and inflammable shale found in almost every part of the world, form but a small portion of their remains. "Between the time of the ancient lycopodite found in the flagstone of Orkney," says Hugh Miller, "and those of the existing club-moss that now scatters its light spores by millions over the dead and blackened remains of its remote predecessor, many creations must have intervened, and many a prodigy of the vegetable world appeared, especially in the earlier and middle periods,-Sigillaria,

Favularia, Knorria, and Ulodendron, that have had no representatives in the floras of later times; and yet here, flanking the immense scale at both its ends, do we find plants of so nearly the same form and type that it demands a careful survey to distinguish their points of difference."

CHAPTER II.

LICHENS.

"Search out the wisdom of nature: there is depth in all her doings. She hath, on a mighty scale, a general use for all things; yet hath she specially for each its microscopic purpose."-MARTIN F. TUPPER.

To most minds the title of this chapter may suggest no idea of importance. Flowers they love, for they are linked with childhood's recollections of sunshine and mirth, and mingle with the hallowed memories of the dead, and of the scenes amid which they are laid. Ferns they admire as they cluster in the forest shade, gracefully bend down to see their own forms in the mossy spring, or wave from some wild inaccessible crag their delicate fronds in the breeze of summer; and mosses they consider beautiful, as they repose their languid limbs, in the sultry noonday, on the woodland banks wreathed in dreamy-looking shadows, to which these tiny plants lend their all of softness and beauty. But the lowly lichens they pass by with indifference, regarding them only as inorganic discolorations and weatherstains on the trees and rocks where they repose. And yet they too are interesting, both as regards their history and their uses; as interesting as many plants which

occupy a far higher position in the ranks of vegetation. Uninviting and apparently lifeless although their external aspect may appear, they are found, when subjected to the microscope, to have their own peculiar beauties and wonders. Simple as is their construction, being entirely composed of an aggregate of minute cells united together in various ways by intercellular matter, and completely destitute of stems, leaves, and all those parts which enter into our ideas of perfect plants, yet by a wonderful compensation they are so extensively diversified in their form and appearance, as to present to the student of nature, a field for his inquiry, as wide and wondrous, as the display of green foliage and blossoms of every hue which glow in the summer sun. To the Pre-Raphaelite landscape painter, intent upon seeking materials for the foregrounds of his sketches, they possess an indescribable interest. Through their instrumentality the miserable hovel, with its rough unmortared walls, becomes a charming and romantic object. The old dyke by the wayside, commonplace and disagreeable although it may look when newly constructed, becomes a pleasing feature in the landscape when garnished with the grey rosettes, eccentric patches, and nebula of the lichens; and the rude, rugged rock acquires an additional wildness and picturesqueness through the affluent display of these plants. Along with the wallflower and the ivy, they decorate the mouldering ruin, and harmonize its otherwise haggard and discordant features, by their subdued and varied colouring, with the gentler forms and the softer tone of the scenery around. Thus nature takes back into her bosom the falling works of human