Vegetation becomes scarce in this region, not, as commonly supposed, because Alpine plants do not here find the necessary conditions for growth, but simply for want of soil. The intense heat of the direct rays of the sun (see chapter iii., pages [76]-[77]) compensates for the cold of the night; and it is probable that the greater allowance of light also stimulates vegetable life. But all the more level parts are covered with ice or snow; and the higher we ascend, the less the surface remains bare, with the exception of the projecting rocks which usually undergo rapid destruction and breaking up from the freezing of whatever water finds its way into their fissures.
Nevertheless, many species of flowering plants have been found even at the height of eleven thousand feet.
It is in this region that plants are found whose true home is in the arctic regions (see chapter ii., pages [64]-[65]).
For the sake of those who love ferns, lycopods, and other cryptogamic or flowerless plants, a few words may be said here. Of the polypodies, the beech fern and oak fern are generally common, so is the limestone polypody in places where limestone occurs. Another species (P. alpestre) very like the lady fern grows plentifully in many places. The parsley fern, familiar to the botanist in Wales and other parts of Great Britain, is common, especially on the crystalline rocks, and ascends to above seven thousand feet. The holly fern is perhaps the most characteristic one of the higher Alps. It is abundant in almost every district from the Viso to the Tyrol, ranging from about five thousand feet to nearly eight thousand feet. The finest specimens are to be found in the limestone districts. Nestling down in little channels worn out of the rock, it shoots out great fronds, often more than eighteen inches long, which are giants compared to the stunted specimens seen on rockwork in English gardens.
Asplenium septentrionale is very common in most of the districts where crystalline rocks abound. The hart's tongue is hardly to be called a mountain fern. The common brake is confined to the lower slopes.
Cistopteris fragillis and C. dentata are common, and the more delicate C. Alpina is not rare. The noble Osmunda regalis keeps to the warmer valleys. The moonwort abounds in the upper pastures.
The club-mosses (Lycopodium), which are found in Great Britain, are common in most parts of the Alps, especially the L. selago, which grows almost up to the verge of the snows. Lower down is the delicate L. velveticum, which creeps among the damp mosses under the shade of the forest. Many of the smaller species stain with spots of crimson, orange, and purple the rocks among the snowfields and glaciers, and gain the summits of peaks more than eighteen thousand feet above the sea, reaching even to the highest rocks in the Alpine chain. For the sake of readers who are not familiar with that wonderful book, "Modern Painters," we will quote some exquisite passages on lichens and mosses, full of beautiful thoughts:—
"We have found beauty in the tree yielding fruit and in the herb yielding seed. How of the herb yielding no seed,—the fruitless, flowerless[17] lichen of the rock?
"Lichens and mosses (though these last in their luxuriance are deep and rich as herbage, yet both for the most part humblest of the green things that live),—how of these? Meek creatures!—the first mercy of the earth, veiling with trusted softness its dintless rocks, creatures full of pity, covering with strange and tender honour the scarred disgrace of ruin, laying quiet finger on the trembling stones to teach them rest. No words that I know of will say what these mosses are; none are delicate enough, none perfect enough, none rich enough. How is one to tell of the rounded bosses of furred and beaming green; the starred divisions of rubied bloom, fine-filmed, as if the Rock Spirits could spin porphyry as we do grass; the traceries of intricate silver, and fringes of amber, lustrous, arborescent, burnished through every fibre into fitful brightness and glossy traverses of silken change, yet all subdued and pensive, and framed for simplest, sweetest offices of grace? They will not be gathered, like the flowers, for chaplet or love token; but of these the wild bird will make its nest and the wearied child his pillow.
"And as the earth's first mercy, so they are its last gift to us. When all other service is vain, from plant and tree the soft mosses and grey lichen take up their watch by the headstone. The woods, the blossoms, the gift-bearing grasses, have done their parts for a time, but these do service for ever. Tree for the builder's yard—flowers for the bride's chamber—corn for the granary—moss for the grave.