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BOTANY 2. The Cherwell District The boundaries of this district are as follows : From Charwelton to the Warwick- shire border near Marston Hill it is bounded by the Avon district as already described ; from this point near Marston Hill to the Three-shire Stone, near Wormleighton reservoir, its western limit is the county boundary of Warwickshire. At the Three Mile Stone Oxford- shire takes the place of Warwickshire, and the county boundary limits our district on the west as far south as Aynhoe. It then also forms our boundary on the south along a line which may be traced across country to the Cottisford racecourse on the Brackley turnpike road, and then follows that road to the ' Barley Mow ' Inn, where it touches the water-parting of the Ouse. From the ' Barley Mow,' near Evenley, our separating line is drawn along the Brackley road to Evenley, and then along the road to King Sutton as far as to Rowler Farm, when a northerly direction is taken towards Farthinghoe, leaving Hinton-in-the-Hedges in the Ouse district to the east, and then taking in Farthinghoe, it passes between Marston St. Lawrence and Gretworth, the latter being in the Ouse district. As we proceed northwards the boundary line is traced along the high ground to the east of Thorpe Mandeville, Culworth and Moreton Pinkney to Adston, Preston Field, Preston Capes, and Charwelton. From Preston Capes to Charwelton the Nene district forms its northern boundary. The Cherwell issues from a spring rising in the cellar of Charwell House from an elevated table-land of Lias capped here and there by outliers of Oolite at an altitude of over 500 feet above the level of the sea, and from this table-land springs send their waters respectively to the German Ocean and the Bristol Channel. At Charwelton, on the Marlstone, the infant Cherwell is crossed by a picturesque and interesting stone horse-bridge. Then it flows by Woodford and Edgcott and the ancient battlefield of Danesmoor, near which at Ayles Mill it enters Oxfordshire. A few miles south of this at Chacombe the Cherwell divides the counties of Oxford and Northampton as far south as to Aynhoe, flowing through alluvial meadows resting on the Lower Lias clay. Above Chacombe comes in the Warwick- shire branch of the river, and other feeders from both sides of the valley, which has hitherto consisted of a broadly undulating tract, but now assumes a more contracted character, and the river cuts through ridges of more unequal elevation. It passes Banbury (where the datum mark is about 300 feet above sea-level) and the river, which has cut its way down to the Liassic rocks, passes King Sutton and the well wooded park of the Cartwrights near Aynhoe, where a small brook, which rises near Evenley Castle and passes by Croughton, and the southern part of Aynhoe Park, forms the county boundary. The Cherwell now becomes wholly an Oxfordshire stream, and at Oxford merges with the Thames at a spot where the river is about I go feet above sea-level. The catchment basin of the whole of the Cherwell valley is estimated as about 500 square miles. The Cherwell district has its counterpart in Warwickshire, and Mr. Bagnall has made the portion drained by this stream District 10 of his Flora of IVarwichhire ; the highest ground in the district in that county being a portion of Edgehill, 766 feet above the sea-level. Mr. Bagnall complains that his district is rather poor in interesting species, but he records a willow-herb [Epilobium roseum) which at present is not known in this county, although very likely to be found. The Cherwell district corresponds also to the districts called the Swere or Upper Cherwell and the Ray or Lower Cherwell of my Flora of Oxfordihire, but these are much larger than the Northamptonshire district and con- tain several species not recorded for our county. One of these, the water avens [Geum rivale), so far as Oxfordshire is concerned, practically confined to the Cherwell basin, being rather frequent by the river only a short distance from the Northamptonshire boundary, and I do not yet despair of adding it to our county list. Among the other plants found in Oxfordshire which we lack are Rosa agrestis {R. sfpium), R. systyla, Pulicaria vulgaris, Juniperus communis, Anthemis nobilis, Arabis perfoliata, Viola palustris, Vicia lathyroides, and Car ex axillaris. Notwithstanding the absence of these species, this district is quite an interesting one, as there is considerable variety in the geological formations from the Lower Lias clay to the Marlstone, Upper Lias clay, Northampton sands, and the Great Oolite, and the latter is in places covered with drift. Although there is no great extent of woodland, there are some interesting spinneys, while a few portions of bog still remain. One of these owes its existence to a patch of drift clay overlying the Great Oolite near Evenley. Although this piece of bog is very small, it is remarkable how many species which are absent from the greater portion of the district are still to be found in it. The beautiful grass of Parnassus {Parnassia palustris) still lingers there with the marsh helleborine {Epipactis palustris), the grass Molinia varia, the 59