BOTANY 



garis as the variety Jilicaulis] ; in another, kept permanently wet by the 

 copious springs, we have the golden saxifrage (Cbrysosplenium oppositifolium), 

 and even this list does not exhaust the number. 



The Greensand stretches out by Heath and Reach to Leighton 

 Buzzard, and is overlapped by the Gault near Fenny Stratford. There 

 are small outlying patches on Muswell Hill and at Brill, and it also caps 

 Quainton Hill. Beds of rich phosphatic coprolites are also found in it 

 occasionally. 



THE GAULT, unlike the Lower Greensand, is a continuous formation 

 which stretches from the Oxfordshire border across Buckinghamshire to 

 the Bedfordshire border near Eaton Bray, and in its progress widens from 

 three miles near Towersey to seven miles on the eastern side. Near the 

 Dunstable downs at Edlesborough a bed of black coprolites is found about 

 fifty feet below the surface of the Gault, which exists usually as a thick 

 mass of pale blue clay, often with greyish-brown phosphatic nodules. 

 The stiff, heavy soil formed by it is usually flat and featureless, resembling 

 the two previous impervious formations in being deficient in interesting 

 species. Those characteristic of the Oxford and Kimeridge Clays are 

 also common to this. 



THE UPPER GREENSAND overlies the Gault and stretches from 

 Princes Risborough and Henton to about a mile north-east of Buckland, 

 from which place it thins out so as to be not easily traced, but it is to be 

 seen in a brickyard at Eaton Bray. Its junction with the Gault is marked 

 by a series of springs which are thrown out by the impervious nature of 

 the Gault, and near them are situated at short intervals numerous villages, 

 while the copious streams of clear pure water are largely used for the 

 cultivation of water cress, which is sent in great quantity to London and 

 other large towns. One of these springs issues out of the romantic 

 Bledlow Gorge, which furnishes a scene quite unique in the county. 

 The golden saxifrage (Cbrysosplenium oppositifolium) grows there, and is 

 a very rare plant in the county. 



THE CHALK formation is one of the principal strata which come 

 to the surface in the county, not only from the extent of surface 

 which it occupies, but from the conspicuous feature caused by the 

 rather bold northern escarpment of the Lower Chalk with its indented 

 bays, which from a distance give it the appearance of an old coast- 

 line, but closer examination reveals the fact that its configuration is 

 not the result of marine but of subaerial denudation, and that in every 

 age it has only been the waves of wind, rain and mist which have 

 surged against it, and carved out indentations which mark its contour 

 in its course from Bledlow to the downs near Eaton Bray. The upper 

 part is formed of a thin but very hard and pinkish bed of Chalk rock 

 resting on other beds of chalk of different degrees of porosity and 

 density, but entirely free from flints. Near the base is a very hard 

 deposit called Totternhoe Stone, and beneath this is a softish white 

 chalk marl, which forms the rising ground between Bledlow, Princes 

 Risborough, etc., and is often under agrarian culture. The abrupt 



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