INTRODUCTION. XXXVI 
and Holton woods. Here comes in a brook which rises on the 
north side of Shotover, at first its waters being half choked by 
Chrysosplenium, but gathering force on its way it forms the 
ornamental waters at Shotover House, and passing near Holton 
quarries, once the locality for the Spider Orchis, then flowing 
eastwards to the south of Holton wood, it joins the Boarstall 
stream, meeting the Thame near Holton Mill. That river enter- 
ing Oxfordshire at Thame, forms the boundary between Oxon 
and Bucks, by Shabbington, north of Waterperry, where leaving 
Bucks it turns south by Waterstock, Wheatley, and Cuddesdon. 
South of Cuddesdon it receives the LHaseley brook, which has 
drained a considerable extent of country from Adwell, Tetsworth, 
Haseley and Little Milton. Shortly afterwards, near Chiselhampton, 
comes in the Chalgrove brook, issuing like the former stream from 
the chalk near Lewknor, and draining Cuxham, Chalgrove, Ascot, 
and Stadhampton. South of Chiselhampton the Thame receives 
from the north the Baldon brook, which rises near Garsington, 
and flows by Toot and Marsh Baldon. The Thame then passes 
Newington and Drayton and flows by the fine abbey church of 
8. Birinus at Dorchester to the Thames, which now proceeds 
southwards by Shillingford, Bensington, and Wallingford, to 
the fine old elms of Mongewell. 
Besides the Thame the Thames in its progress from Oxford 
has received a few small feeders, in themselves unimportant, yet 
the first interesting from the fact that it drains the south side 
of Shotover, Bullingdon Green and Cowley Marsh. This 
forms one of the most varied and prolific excursions to the 
Oxford botanist, only yielding to the Stow Wood and Headington 
excursion in the richness of its flora. The plants recorded 
from the above-mentioned places are as follows :—Ranunculus 
parviflorus, Aquilegia, Arabis hirsuta, Lepidium heterophyllum, 
Alsine tenuifolia, Spergularia rubra, Montia, Androsemum, 
H. humifusum, H. pulchrum, Geranium rotundifolium, G. pyre- 
naicum, Trifolium subterraneum, T. striatum, T. scabrum, 
Ornithopus, Lathyrus Nissolia, L. sylvestris, Hippocrepis, Orobus 
tuberosus, Spirea Filipendula, Potentilla procumbens, Rubus 
rhamnifolius, cordifolius, R. thyrsoideus, leucostachys, ampli- 
ficatus, Salteri, rudis, Radula, preruptorum, Koehleri, pallidus, 
glandulosus, Rosa tomentosa, rubiginosa, micrantha, Pyrus 
