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 BOTANY Cold Ash Common is 513 feet above the sea. The watershed of the Pang and the Kennet near Englefield is nearly 300 feet above the sea. In the following pages, which by the kind permission of the dele- gates of the Clarendon Press at Oxford I have been allowed to compile from my Flora of Berkshire published by them in 1897, 1 shall endeavour to give a general idea as to what species are native of the county, and of those which are, although not indigenous, yet now well established, and to show roughly their distribution through its area, for which purpose various botanical districts essentially based upon the river drainage have been made. The boundaries of these districts will be briefly described, and a list of the more interesting species occurring in each district will be enumerated ; but for those who seek a more intimate acquaintance with the distribution of plants through the county, and an account of the various local forms and varieties, or for a complete Botanologia of those botanists who have assisted to bring our knowledge of the county flora to its present state of completeness, my Flora of Berkshire already alluded to should be consulted. The following tables show the number of species which have been reported on good authority to have been seen growing in a wild state in the counties surrounding Berkshire, as well as those compiled for the county by myself : Berkshire Oxfordshire Bucks Native plants. . 898 . . 847 . . 818 Denizens. ... 46 .. 49 .. 25 Colonists .... 56 .. 43 .. 34 Total. . 1,000 939 877 The word native, as used above, signifies the grade of citizenship of the plant in Berkshire, namely an aboriginal species ; denizen means that although the plant at present maintains its habitat, as if a native, without the aid of man, yet it is liable to some suspicion of having been originally introduced, for example the common elm ; while colonist suggests a weed of cultivated land, or about houses, and seldom found except in places where the ground has been adapted for its production by the operation of man, as the red poppy (Papaver Rhceas). Besides these species about 400 named varieties and forms, and about 70 hybrids, and over 200 species not native in Britain, or of casual occurrence or planted in Berkshire, have been observed. The total number of species native in the British Isles is about 1,750, and about 250 of colonists, denizens and aliens are also included in our British lists ; but of these 144 are confined to the neighbourhood of the sea, 17 are confined to Ireland, about 20 to the Channel Isles, while 200 are plants of northern latitudes, or are not found so far south as Berk- shire except in mountainous situations. It will be observed that after making these reductions about 1,350 species remain which might occur in the county ; yet we find from the 29