A HISTORY OF ESSEX 



appear the marine species occurs also high up on mountains. Common 

 thrift (Armeria marifima), which grows abundantly on our saltings, covered 

 at every tide by salt water, also flourishes high up on mountains, where 

 the conditions of soil and climate must be very different ; in fact it is 

 difficult to imagine localities affording wider differences. In the sea 

 plantain (Plantago maritima) and scurvy grass (Cochlearia officinalis] we 

 have also two plants which flourish on our saltings and high up on 

 mountains. 



The species of Atriplex on our coast should also provide material for 

 investigation. On our sandy shores there is a wide range of variations, 

 and inland another series of variations. The sandworts (Spergularia) 

 give four forms : S. rubra^ growing in hot, sandy, inland situations ; 

 S. sa/igna, found in muddy or rocky situations by the sea ; S. media, 

 occurring on muddy sea marshes; and lastly a species found only in 

 rocky places by the sea, S. rupestris. It is scarcely necessary to say that 

 this latter does not occur in Essex. These plants are so closely related 

 that botanists do not agree in dividing them into species and varieties, 

 but the inland forms are quite distinct from the marine forms. It will 

 thus be seen that the coast flora of Essex offers problems of great 

 scientific interest. 



Insectivorous plants mostly occurring in bogs are represented in 

 the county, though rare. We have the sundew (Drosera rotundifolia), 

 the great bladderwort (Utricularia vulgaris), rue-leaved saxifrage (Saxi- 

 fraga tridactylites), and that remarkable plant the tooth wort (Lathraa 

 squamaria), which obtains its vegetable diet from the roots of plants to 

 which it attaches itself, and its animal nourishment by catching small 

 insects in its scale-like leaves, folded back at the edges to form traps for 

 unwary insects. The plant only needs to come above the ground in the 

 spring to form flowers and seeds, not requiring green leaves like other 

 plants. 



Orchids remarkable for the mechanism of their flowers by which 

 their fertilization is accomplished are well represented in the county, 

 though not so abundant as in some of the southern counties of England. 



The poisonous plants growing in the county are both of scientific 

 and also of practical interest to the farmer and country resident. They 

 may be summarized as follows : The poppy, which is unwholesome, 

 though not so deadly as those species favouring hot climates ; the com- 

 mon celandine, which is an acrid and violent irritant ; the soapwort ; the 

 Deptford pink ; the white campion, the red campion, and most plants 

 of the natural order Caryophylleas, which contain the active principle 

 saponine and are therefore either poisonous or unwholesome. Fortunately 

 saponine is destroyed by heating, hence flour made from corn containing 

 seeds of these plants is rendered harmless by cooking. Holly berries 

 cause violent irritation of the bowels. The leafless vetchling (Latbyrus 

 ap/jaca), the rough-podded vetchling (L. birsutus], and the broom (Cytisus 

 Scoparius) are the only British plants of the pea-flower tribe which have 

 been known to possess deleterious qualities, causing violent headache 



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