BOTANY 



London Clay is much more continuous, especially from Crookham nearly 

 to Reading. It also occupies a large area between Reading and Windsor. 

 The country formed by it is often flat, but the well marked range of hills 

 on the south near Binfield, Winkfield, Warfield and Snow Hill in 

 Windsor Great Park belong to the same formation, and the hills of 

 Ashley, Bowsey and Crazey, where the London Clay reaches 454 feet, 

 its highest elevation in the county, although at their base are composed 

 of the Reading Beds, are thickly covered by London Clay. These hills 

 form striking objects which can be seen for many miles off, and are 

 rendered more conspicuous and beautiful from their being covered with 

 wood up to the top. Both Bowsey and Ashley Hills are capped with 

 pebble gravel. This and other drift gravels make the vegetation of the 

 London Clay more varied than it would otherwise be, and the old 

 sylvan vegetation has contributed in turn to make it more extensive by 

 the deposits of peaty growth with which it is sometimes overlaid, 

 while its situation in many cases at the base of the Bagshot Beds again 

 help to contribute to the variety of species. Instances of peat-loving 

 species are the royal fern (Osmunda regalis] ; the sedges Carex elongata, 

 C. elata (C. stricta), C. pulicaris, C. Pseudo-cyperus, C. echinata, etc. ; the 

 sundews Drosera longifolia and D. rotundifolia ; the Lancashire asphodel 

 (Narthecium ossifragum], and the deer's grass (Scirpus ccespitosus) . The 

 combination of gravel overlying a peaty gravel is especially conducive 

 to the occurrence of such plants as the all-seed (Millegrana Radiola], the 

 chaffweed (Centunculus minimus], the lesser skull-cap (Scutellaria minor) 

 and others. More distinctly argillaceous species are the grass Alopecurus 

 fufous, the bur marigold (Bidens cernua), the knot grasses Polygonum 

 minus and mite, the reed mace (Typba angustifolia), the orchid Orchis 

 latifolia, and the sedges C. vesicaria and C. axillaris, 



THE BAGSHOT BEDS. In its upper part the London Clay grows 

 sandy and passes into a very variable group, to which this name is given. 

 It consists of alternations of sands, greensands, pebble beds and clays, 

 and is subject to many local variations as it is traced from place to place. 

 Its junction with the London Clay is marked by springs, the water of 

 which has percolated through the porous Bagshots till it is thrown out 

 by the impervious clay on which it rests, and in such places a bog is 

 formed with a vegetation essentially dissimilar from the dry, porous 

 and more elevated gravelly and sandy hillocks of the Bagshot sands, so 

 that in a few steps one- passes from the heaths and their accompanying 

 parasite the dodder, the dwarf furze, the brambles and hawkweeds and 

 grasses Descbampsia Jiexuosa, Aira caryopbyllea, A. preecox, the foxglove 

 (Digitalis purpurea), the St. John's wort (Hypericum pulcbrum] and the 

 cudweed (Gnaphalium syfoaticum) to a sphagnum bog with its sundews, 

 Lancashire asphodel, smaller skullcap, its sedges Ryncbospora alba, Scirpus 

 ccespitosus, Juncus bulbosus (supinus), etc., and in the wettest portion we 

 may see the bogbean (Menyantbes], the floating club rush (Scirpus Jiuitans) , 

 the cotton grass (Eriopborum angustifolium), the sedge Carex rostrata, 

 and the marsh St. John's wort (Hypericum Elodes). 



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