A HISTORY OF ESSEX 



(Gentiana amarelld), deadly nightshade (Atropa Belladonna), the dwarf 

 orchis (Orchis ustulatd), the pyramidal orchis (O. pyramidalis), the green 

 man orchis (Aceras anthropophord) , bee orchis (Opbrys apiferd), spider 

 orchis (O. araniferd), the fly orchis (O. musciferd), large white helle- 

 borine (Cephalanthera pat/ens), and other chalk plants. 



London clay is perhaps remarkable for the limited character of its 

 flora. In the summer the surface dries and becomes so hard that a pick 

 can scarcely penetrate it, whilst below it retains much moisture. It 

 favours those plants which send their roots deep into the soil, e.g. colts- 

 foot (Tussilago Farfard), which is common on undrained London clay. 

 Thymus Chamcedrys also favours this formation, whilst wild oat (Avena 

 fatud] is peculiarly abundant on it. 



The gravels and sands possibly stand next to chalk for the variety 

 of characteristic plants which these soils produce in the county. The 

 following may be mentioned as characteristic of these formations : the 

 interesting mouse's-tail (Myosurus minimus), the small-flowered ranunculus 

 (Ranunculus parviflorus) , flixweed (Sisymbrium Sophia], swine's cress (Sene- 

 biera Coronopus), lesser swine's cress (S. didymd), dog violet (Viola canind), 

 Deptford pink (Dianthus Armerid), English catchfly (Silene anglicd), purple 

 sandwort (Spergula rubrd), trailing St. John's wort (Hypericum humifusum), 

 upright St. John's wort (H. pulchrum), allseed (Radio/a millegrand), needle 

 whin (Genista anglicd), hare's foot trefoil (Trifolium aruense), lesser trefoil 

 (T. minus), slender trefoil ( T. Jiliforme), annual knawel (Scleranthus annuus), 

 purple-tipped cudweed (Filago apiculatd), field cudweed (F. minima), 

 narrow-leaved cudweed (F. Gallicd), slender-flowered thistle (Carduus 

 tenuiftorus), common sheep's scabious (Jasione montand), downy hemp 

 nettle (Galeopsis ochroleucd), and the pretty little orchid 'lady's tresses' 

 (Spiranthes autumnalis] . 



The riverside and alluvium flora is well represented ; amongst these 

 plants we have the common meadow-rue (Thalictrum flaiium), greater 

 spearwort (Ranunculus Lingua), white water lily (Nymphcea alba), yellow 

 water lily (Nuphar luteuni), bitter ladies' smock (Cardamine amard), purple 

 loosetrife (Lythrum Salicaria, L.), the willow herbs (Epilobium), common 

 hare's-tail (Hippuris vu/garis), whorled water-milfoil (Myriophyllum verti- 

 cillatum), spiked water -milfoil (M. spicatum), meadow-sweet (Spiraea 

 Ulmarid), common marsh wort (Helosciadium nodiflorum), the very poisonous 

 water drop worts (CEnanthe), common valerian (Valeriana qfficinalis), small 

 teasel (Dipsacus pilosus], hemp agrimony (Eupatorium cannabinum), bur 

 marigold (Bidens tripartita and B. cernud), yellow rattle (Rhinanthus 

 Crista-galli), most species of the mints (Mentha rotundifolia, M. aquatica, 

 M, syhatica, M. viridis, M. piperita, M. pratensis, M. sativa), scullcap 

 (Scute llaria galericulatd), water violet (Hottonia palustris), yellow loosestrife 

 (Lysimachia vu/garis), great water dock (Rumex Hydrolapathum), yellow 

 flag (Iris pseudacorus], great flowering rush (Butomus umbellatus), sweet 

 flag (Acorus Calamus), all the duckweeds (Lemnd), and bullrush (Scirpus 

 lacustris) . 



Essex possesses a very representative marine flora. There are 



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