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 being known. Four regions may be distinguished: the Arctic, the Forest, the Steppe and the Circum-Mediterranean.

The Arctic Region comprises the tundras of the Arctic littoral beyond the N. limit of the forests, which closely follows the coastline, with deviations towards the N. in the river valleys (70° N. in Finland and on the Arctic Circle about Archangel, 68° N. on the Urals, 71° in W. Siberia). The shortness of the summer, the deficiency of drainage and the depth to which the soil freezes in winter, are the circumstances which determine the characteristic features of the vegetation of the tundras. Their flora is far closer akin to the floras of N. Siberia and N. America than to that of central Europe. Mosses and lichens are distinctive, as also are the birch, the dwarf willow and several shrubs; but where the soil is drier, and humus has been able to accumulate, a variety of herbaceous flowering plants, some of them familiar in W. Europe, make their appearance. Only 275 to 280 phanerogams are found within this region.

The Forest Region of the Russian botanists includes the greater part of the country, from the Arctic tundras to the steppes, and over this immense expanse it maintains a remarkable uniformity of character. Beketov subdivides it into two portions—the forest region proper and the “Ante-Steppe” (predstepie). The N. limit of the ante-steppe is represented by a line drawn from the Pruth through Zhitomir, Kursk, Tambov and Stavropol-on-Volga to the sources of the Ural river. But the forest region proper presents a different aspect in the N. from that in the S., and must in turn be subdivided into two parts—the coniferous region and the region of the oak forests—these being separated by a line drawn through Pskov, Kostroma, Kazañ and Ufa. Of course the oak occurs farther N. than this, and coniferous forests extend farther S., advancing even to the border-region of the steppes. To the N. of this line the forests are of great extent and densely grown, more frequently diversified by marshes than by meadows or cultivated fields. Vast and impenetrable forests, impassable marches and thickets, numerous lakes, swampy meadows, with cleared and dry spaces here and there occupied by villages, are the leading features of this region. Fishing and hunting are the most important sources of livelihood. The characteristics of the oak region, which comprises all central Russia, are totally different. The surface is undulatory; marshy meadow lands no longer exist on the flat watersheds, and only a few in the deeper and broader river valleys. Forests are still numerous where they have not been destroyed by the hand of man, but their character has changed. Conifers are rare, and the Scotch pine, which is abundant on the sandy plains, takes the place of the Abies. The forests are composed of the birch, oak and other deciduous trees, the soil is dry, and the woodlands are divided by green prairies. Viewed from rising ground, the landscape presents a pleasing variety of cornfield and forest, while the horizon is broken by the bell-towers of the numerous villages strung along the banks of the streams.

Viewed as a whole, the flora of the forest region is to be regarded as European-Siberian; and, though certain species disappear towards the E., while new ones make their appearance, it maintains, on the whole, the same features throughout from Poland to Kamchatka. Thus the beech (Fagus sylvatica) is unable to survive the continental climate of Russia, and does not penetrate beyond Poland and the S.W. provinces, reappearing again in the Crimea. The silver fir does not extend over Russia, and the oak does not

cross the Urals. On the other hand, several Asiatic species (Siberian pine, larch, cedar) grow freely in the N.E., while numerous shrubs and herbaceous plants, originally from the Asiatic steppes, have found their way into the S.E. But all these do not greatly alter the general character of the vegetation. The coniferous forests of the north contain, besides conifers, the birch (Betula alba, B. pubescent, B. fruticosa and B. verrucosa), which extends from the Pechora to the Caucasus, the aspen, two species of alder, the mountain-ash (Sorbus aucuparia), the wild cherry and three species of willow. S. of 62°-64° N. appears the lime tree, which multiplies rapidly and, notwithstanding the rapidity with which it is being exterminated, constitutes entire forests in the east (central Volga, Ufa). Farther S. the ash (Fraxinus excelsior) and the oak make their appearance, the latter (Quercus pedunculata) reaching in isolated groups and single trees as far N. as St Petersburg and South Finland (Q. Robur appears only in the S.W.). The hornbeam is prevalent in the Ukraine, and the maple begins to appear in the S. of the coniferous region. In the forest region no fewer than 772 flowering species are found, of which 568 dicotyledons occur in the Archangel government (only 436 to the E. of the White Sea, which is a botanical limit for many species). In central Russia the species become still more numerous, and, though the local floras are not yet complete, they number 850 to 1050 species in the separate governments, and about 1600 in the best explored parts of the S.W. Corn is cultivated throughout this region. Its N. limits advance almost to the Arctic coast at Varanger Fjord, farther E. they hardly reach N. of Archangel, and the limit is still lower towards the Urals. The N. boundary of rye closely corresponds to that of barley. Wheat is cultivated in S. Finland, but in W. Russia it hardly gets N. of 58° N. Its true domains are the oak region and the steppes. Fruit trees are cultivated as far as 62° N. in Finland, and as far as 58° in the E. Apricots and walnuts flourish at Warsaw, but in Russia they do not thrive beyond 50°. Apples, pears and cherries are grown throughout the oak region.

The Region of the Steppes, which is coincident with the whole of S. Russia, may be subdivided into two zones—an intermediate zone and that of the steppes proper. The ante-steppe of the preceding region and the intermediate zone of the steppes include those tracts in which the W. European climate contends against the Asiatic, and where a struggle is carried on between the forest and the steppe. It is comprised between the summer isotherms of 59° and 63°, being bounded on the S. by a line which runs through Ekaterinoslav and Lugañsk. S. of this line begin the steppes proper, which extend to the sea and penetrate to the foot of the Caucasus.

The steppes proper are very fertile, elevated plains, slightly undulating, and intersected by numerous ravines which are dry in summer. The undulations are scarcely apparent. Not a tree is to be seen, the few woods and thickets being hidden in the depressions and deep valleys of the rivers. On the thick layer of black earth by which the steppe is covered a luxuriant vegetation develops in spring; after the old grass has been burned a bright green prevails over immense stretches, but this rapidly disappears under the burning rays of the sun and the hot E. winds. The colouring of the steppe changes as if by magic, and only the silvery plumes of the steppe-grass (Stipa pennata) wave in the wind, tinting the steppe a bright yellow. For days together the traveller sees no other vegetation; even this, however, disappears as he approaches the regions recently left dry by the Caspian, where saline clays, bearing a few Salsolaceae, or mere sand, take the place of the black earth. Here begins the Aral-Caspian desert. The steppe, however, is not so devoid of trees as at first sight appears. Innumerable clusters of wild cherries (Prunus Chamaecerasus), wild apricots (Amygdalus nana), the Siberian pea-tree (Caragana frutescens), and other deep-rooted shrubs grow at the bottoms of the depressions and on the slopes of the ravines, imparting to the steppe that charm which manifests itself in the popular poetry. Unfortunately the spread of cultivation is fatal to these oases (they are often called “islands” by the inhabitants); the axe and the plough ruthlessly destroy them.

The vegetation in the marshy bottoms of the ravines and in the valleys of the streams and rivers is totally different. The moist soil encourages luxuriant thickets of willows (Salicineae), surrounded by dense chevaux-de-frise of wormwood and thorn-bearing Compositae, and interspersed with rich but not extensive prairies, harbouring a great variety of herbaceous plants; while in the deltas of the Black Sea rivers impenetrable beds of reeds (Arundo phragmites) shelter a forest fauna. But cultivation rapidly changes the physiognomy of the steppe. The prairies are superseded by wheat-fields, and flocks of sheep destroy the true steppe-grass (Stipa pennata).

A great many species unknown in the forest region make their appearance in the steppes. The Scotch pine still grows on all sandy spaces, and the maple (Acer tatarica and A. campestre), the hornbeam and the black and white poplar are very common. The number of species of herbaceous plants rapidly increases, while beyond the Volga a variety of Asiatic species are added to the W. European flora.

The Circum-Mediterranean Region is represented by a narrow 