BOTANY 



Overlying the London clay we have various formations consisting 

 of sands and gravels. Amongst these are: (i) Bagshot beds, which 

 constitute some of the higher and more picturesque tracts, as at High 

 Beech, Brentwood, Warley, Billericay, Stock, Langdon Hill and Ray- 

 leigh ; (2) the glacial gravels occurring at Quendon, at Clavering, at 

 Harlow and at Roydon, along the Colne from Great Yeldham, Halstead, 

 Gosfield, Great Bardfield, Thaxted, over the high grounds of Danbury, 

 around Colchester, Brightlingsea and St. Osyth, in patches at Mersca 

 Island and Tolleshunt, and at Tiptree Heath ; (3) valley gravel in the 

 Thames valley. 



Boulder clay, another glacial drift formation, occupies a large 

 portion of the surface of Essex. 



Bordering on our rivers we have large tracts of alluvium recently 

 deposited, forming extensive marshlands. These marshlands near the 

 sea and riverine estuaries are either covered at high tides, when they are 

 known as saltings, or the sea water permeates them, when they may be 

 described as brackish marshes. We have also on the edges of the sea 

 coast considerable stretches of shingle and sand. The long stretches 

 of sea wall protecting the coast have a characteristic though limited 

 flora. 



It will therefore be evident that Essex has an abundant variety of 

 soil, and is very pleasantly diversified with arable land and pasture, with 

 woodlands, commons and well timbered hedgerows. It includes every 

 species of soil from the most stubborn to the mildest loam. 



For our present purposes we may group the geological formations 

 as follows : 



1 . Chalk and Boulder Clay, which contains much chalk. 



2. London Clay. 



3. Gravels and Sands. 



4. Alluvium. 



5. Marine. 



Though chalk only comes to the surface over a small area in the 

 county the chalk flora extends over a considerable portion of its surface, 

 for the Essex boulder clay usually contains so much chalk that the chalk 

 loving plants may always be met with upon this formation. It is upon 

 this strata that the traveller's joy (Clematis Vitalba] flourishes more 

 particularly. Both the green hellebore and the foetid hellebore also 

 occur as natives upon the boulder clay. Berberis vu/garis is found at 

 Saffron Walden on the chalk, also the common rockrose (Helianthemum 

 uulgare), which plant also occurs at other stations. The hairy violet 

 (Viola hirta) is common both upon the chalk and upon the boulder 

 clay. The following chalk plants are included in our flora : the buck- 

 thorn (Rhamnus c atharticus) , ladies' fingers (Anthyllis Vu Ineraria) , the 

 wild liquorice (Astragalus glycypbyllos), the purple milk-vetch (A. hypo- 

 glottis'), the dropwort (Spiraea Filipendula), the salad burnet (Poterium 

 Sanguisorba], common hare's ear (Bupleurum rotundifoliuni) , dwarf thistle 

 (Carduus acau/is), yellow-wort (Cblora perfoliata), autumnal gentian 



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