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BOTANY the Thames divides it from Oxfordshire as far as Henley, and thence on the south-eastern side from Bucks between Henley and Old Windsor. Southwards its boundary is often of an arti- ficial character, but from Old Windsor to Blackwater the county boundary of Surrey is the line of limitation. From Blackwater to Thatchams Ford near Swallowfield the river Black- water separates it from Hampshire, and thence to the Forward Road the county boundary of Hants is its western limit. The district is the least homogeneous of all the botanical divisions of the county. It has four well marked kinds of soil. First, that of the heathy, sandy tract of country such as is found round Wokingham and Sandhurst ; secondly, that of the flat clay-land about Rus- combe ; thirdly, that of the hilly chalk country of Wargrave and Cookham ; and lastly, that of the elevated knolls of London clay, often capped by gravel, to be seen at Ashley, Crazey, and Bowsey Hills. But these by no means represent all the varieties of soil. The drainage of the district is complex and often obscure, since a great extent of the area is below 150 feet. The highest point reached by the London clay is at Bowsey Hill, 450 feet, and Easthamp- stead Plain is 430 feet. The Blackwater where it enters the county is about 200 feet, and its outfall into the Thames is about 150 feet above sea level, and the scenery in its course is essentially different from that found in the Isis, Ock, Pang or northern part of the Kennet districts, consisting as it does of extensive tracts of heathy ground planted with pines, which seed freely, stretching in various directions for a considerable distance, and include in fact the hilly country leading up to Easthampstead Plain, Wickham Bushes, Broadmoor and Crow- thorn, the country south of the long Roman road known as the Devil's Highway, and that which lies about Long Moor, Wellington College and the beautiful Finchhampstead Ridges. From the summit of one of the rounded hills the view is over a stretch of dark pine planta- tions covering the lower eminences, or else over an expanse of heather and gorse showing here and there green patches where the sphagnum growth denotes boggy ground. And the vegetation, as has already been stated, is quite as different as the geology or the scenery. In the damper parts, as under Finchampstead Ridges, the birch is plentiful, and in one or two of the wooded portions we may get the Pyrola minor or winter green. The berry-bearing alder (Rhamnus Frangula) replaces R. catharticus, so common on the chalk, and the sweet gale (Myrica Gale) here and there may be found. Two species of sundew grow on the boggy parts, and a rich uliginal vegetation is found, including Illecebrum verticillatum, only known from Devon and Cornwall elsewhere in the British Isles. In the ponds I have found both species of Elatine, E. hexandra and a variety which I have called sessilis, and E. Hydropiper, and the mud wort (Limosella aquatica), but very sparingly. The sedge vegetation is rich and varied, including C, elongata, C. pulicaris, C. canescens, C. turfosa, a hybrid probably of C. data (stricta) with Gordenawii (vu/garis), C. vesicaria, C. rostrata, Rynchospora alba and Schcenus. The form of Veronica scutellaria which occurs is usually var. villosa ; in the northern part of the county the glabrous form alone occurs. The ponds also occasionally yield the pill wort (Pilularia globulifera and I have found Nitella flexilh also. The shore weed (Lit- torella juncea), which is absent from the county north of the Kennet, often covers the bottom of the ponds with a dense vegetation, and in one instance I am afraid has extirpated Elatine. A small fruited form of the bur-reed, S. erectum var. microcarpum (Neum.), has been noticed, and on one of the moors the beautiful Gentiana Pneumonanthe has been found. The heathy portion offers several species which are unknown in our county north of the Kennet, such as the grass Agrostis setacea, the buttercup (Ranunculus Lenormattdi), the violet V. lactea, the marsh cinquefoil (Potentilla palustris), and some plants which are very rare on the Pang and other districts are not uncommon, such as Genista anglica, Teesdalia, Hypocharis glabra, Anthemis nobilis. The hedge banks have Stellaria umbrosa and very rarely Fumaria pallidiflora and F. muralis, while the stream sides afford Epilobium roseum and hybrids of it. A hawkweed (Hieracium murorum) has been found near Wellington College, and a bell flower (Campanula Rapunculus) has been seen near Sandhurst. The bramble flora is particularly rich, and one at least is unknown elsewhere in the county, i.e. Rubus lentiginosus, Lees, the R. cambricus of Focke. Of the suberect forms R. nessensis, R. fissus, and R. plicatus occur, and R. ericetorum, R. Marskalli, R. cognatus, R. nitidus, R. holerythros, R. carpinifolius, R. rhombifolius, R, silvaticus, R. >uestierii, so far only known in Berks from Sandhurst, R. Sprengelii, R. mucronatus, R. Gelertii, R. infestus, R. Babingtonii, R. Lejeunei var. ericetorum, R. foliosus, R. rosaceus and others. The cultivated fields in the Sandhurst district have yielded Apera Spica-venti, Agrostis nigra, Silene anglica, Arnoseris (limited to this district), Mercurialis annua, Filago apiculata, and Antirrhinum Orontium. The railway embankment gives a home for a few species which are rare elsewhere in the district ; such are 59