pelophilous or clay-loving species; whereas in the meadows of the Lower Thames, where chalk fragments are such common constituents, the ordinary vegetation of the low-lying and rich grass pastures will also contain such plants as the lady's-fingers (Anthyllis Vulneraria), the purple blue Canterbury bell (Campanula glomeratd), the scabious (Scabiosa Columbaria), the hawk's-beard (Pieris bieracioides), and the grasses Bromus erectus, Avena pubescens and Kaeleria cristata, which are distinctly gypsophiles or calcareous species.
The flora of the gravels has been already sufficiently touched upon, but we may add that the lettuce (Lactuca virosa), the small buttercup (Ranunculus paruiflorus), the vetch Vicia Latbyroides, the shepherd's scabious (Jasione montana), the cinquefoil (Potentilla argentea), the calamint (Calamintba officinalis}, the rose (Rosa systyla), the clovers Trifolium arvense, T. striatum and T. subterraneum, the clary (Sahia Verbenaca), the hound's-tongue (Cynoglossum officinale), the vervain (Verbena officinalis), the mullein (Verbascum nigrum), the garlic (Allium vineali), the meadow saxifrage (Saxifraga granulata), the bur parsley (Caucalis nodosa), and the hedge honewort (Carum segetum) have been found on them.
The meadow flora consists of many species, varying to some extent with the rocks of which the alluvium is composed, but there are many plants which flourish well either on clay, gravel on loam, and these we need not attempt to particularize here. We must, however, enumerate among the more local species, the small Polygonum (P. minus), which occurs with the knotted spurrey (Sagina nodosa) by the stream near Chesham, and the American balsam (Impatients biflora or flora}, now completely and abundantly naturalized for many miles along the course of the Colne, especially about Wraysbury; another American species, the monkey flower (Mimulus Langsdorffit), is so plentiful as to form a belt of colour for some distance between Latimers and Chenies; and the grass of Parnassus (Parnassia palustris) finds a home in the meadows near. Near Hambledon the spurge (Euphorbia Esula) has been known to grow for many years, and it is possibly native, while in the Eton meadows the star of Bethlehem (Ornitbogalum umbellatum) and the medick (Medicago arabica) are locally common, and the snowflake (Leucojum cestivum} still occurs in a few parts of the Thames between Henley and Windsor.
In the Bray meadow the bedstraw Galium erectum grows freely, and the great dodder (Cuscuta europa) occurs near Windsor; the ditches also afford the sedges Carex Pseudo-cyperus, C. acuta, C. vesticaria, C. disticha; the water starwort (Callitriche obtusangula), the bladderwort (Utricularia vulgaris), the water violet (Hottonia palustris), the frog-bit (Hydrocbaris Morsus-ranae, the water buttercup (Ranunculus trichopbyllus), the bur marigold (Bidens cernua) and the water dropwort (Œanthe Phellandrium).
THE RIVER DRAINAGE OF BUCKINGHAMSHIRE
For many years past it has been the practice in the best and most complete county floras to subdivide the county they describe into
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