A HISTORY OF BUCKINGHAMSHIRE 



slope of the escarpment is to a great extent covered with aboriginal 

 turf, and it is in this portion that the rich growth of xerophilous 

 calcareous plants is to be found. The comparatively short grass does 

 not overshadow the flowering plants, so that in the early summer we 

 have a very brilliant display of blossom, five distinct shades of yellow 

 being the groundwork in the colour scheme, the deepest being struck 

 by the dark orange-flowered horse-shoe vetch (Hippocrepis comosa) ; the 

 next, but slightly more golden in tint, is caused by the lotus (L. 

 corniculatus) ; then comes a somewhat greenish-yellow sheen where 

 great patches of the golden stonecrop (Sedum acre) occur, and a very 

 pale yellow is created where the lady's-fingers (Anthyllis Vulneraria) 

 displays itself, but the paler tint is not altogether derived from the 

 petals, but in part is caused by the conspicuous calyces, while the 

 fifth species growing in countless thousands of pale-gold blossoms is the 

 rock-rose (Helianthemum Cbamcecistus) with its very fugacious petals ; and 

 as if to vie with them the key-note is repeated in the cornfields, where 

 closely contiguous masses of the white mustard (Brassica alba) glow with 

 a vividness that is almost painful under the bright noonday sun. But 

 there are other plants in the turf besides this chord of yellow-blossomed 

 species ; there are the pinkish-white flowers of the squinancy-wort 

 (Asperula cynanchica), the rosy-pink pyramidal spikes of the orchid (Orchis 

 pyramidalis) , or where a rather more impervious bed of chalk occurs we 

 have the duller purple spikes of the fragrant orchid (Habenaria conopsea), 

 and more sparingly the bee orchid (Opbrys apifera). Here and there the 

 milkwort (Polygala vu/garts), with the flowers varying through different 

 shades of blue to pink or white, may be seen, and it is a little curious and 

 inexplicable why on the Berkshire downs the ubiquitous milkwort is 

 P. ca/carea, which here is extremely local and so much less frequent than 

 the common one. Occasionally, especially on the downs above Ivinghoe, 

 may be seen the yellow blossoms of the field ragwort (Senecio campestris), 

 and not uncommonly the purple blue-flowered Canterbury bell (Campanula 

 glomerata). In very many places bushes of the juniper (Juniperus communis] 

 give a dark green colouring, and this too is exceedingly scarce on the 

 Berkshire downs, although here so plentiful, and not restricting itself to 

 the downs, but stretching inland to such commons as Naphill or Burn- 

 ham Beeches, or the slopes near Medmenham. Bushes of the sweet 

 brier (Rosa Eglanteria) and R. mkrantha are plentiful near Princes Ris- 

 borough and Wendover. Where the turf has been removed the porce- 

 lain-white blossoms of the candytuft (Iberis amara) will probably be 

 seen, and few of the arable fields on the bare chalk are without it. 

 Bordering the beech woods may be seen the white blossoms of the 

 helleborine (Cephalanthera pallens), and in the woodland shade the bird's- 

 nest orchid (Neottia Nidus-avis), and the wall lettuce (Lactuca muralis). 

 But we have not even yet exhausted the constituents of the turf, for the 

 rather pretty grass Kceleria cristata is plentiful, as well as the more 

 striking oat-grasses (Avena pubescent and A. pra tensis] , while the brome 

 (Bromus erectus) is abundant. Later in the season the turf is studded 



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