BOTANY 

 SCALE-MOSSES, LIVERWORTS AND CRYSTALWORTS 



The list of Essex Hepaticas includes only the commonest species, 

 with the exception of Trichocolea tomentella and Ptilidium ci/iare, which 

 are characteristic of subalpine boggy woods and moorlands, and where 

 they occur there must almost certainly be other unrecorded species. 

 The genera Kanft'a, Cephalozia, Lejeunia, yungermannia, Reboulia and 

 Zegatella are almost certain to occur in the county. The list must 

 therefore be considered an imperfect one. 



Frullania dilatata, Dumort Plagiochila asplenioides, Dumort 



Radula complanata, Dumort Aplozia crenulata, Dumort 



Porella platyphylla, Carr & Pears inflata, Huds. 



Ptilidium ciliare, Nees Nardia scalaris, Carr 



Trichocolea tomentella, Ehrh. Pellia epiphylla, Corda 



Lepidozia reptans, Dumort Metzgeria furcata, Dumort 



Scapania undulata, Dumort Aneura multifida, Dumort 



nemorosa, Dumort Marchantia polymorpha, Necs 

 Diplophyllum albicans, Dumort Lunularia vulgaris, Mich. 

 Lophocolea bidentata, Dumort Riccia glauca, Linn. 



heterophylla, Dumort Ricciella fluitans, Braun. 



LICHENS (Lichenes] 



The Epping Forest district of Essex and the neighbourhood of 

 Kelvedon are the only portions of the county from which the lichen 

 flora has been at all fully recorded. It is therefore difficult to estimate 

 what wealth of lichens the county possesses, for there are other districts, 

 such as Hatfield Forest and some well wooded portions of the county, 

 worth investigating. 



Lichens occur more particularly upon trees and upon rocks. The 

 majority of lichens are of extremely slow development, remaining 

 latent except when the moisture and other conditions of the atmosphere 

 are favourable. It is therefore upon comparatively old trees and in 

 situations suitable to their requirements that one would expect to find 

 interesting species. Owing to the former bad management of the 

 Epping Forest, the Rev. J. M. Crombie tells us in 1883 that its lichen 

 flora was not so good as it would be under better conditions, and that 

 the species had diminished in numbers since the time when he first 

 visited it, but I am informed that under the new management of the 

 forest the lichen flora is improving. 



Granitic sandstone and calcareous rocks which some lichens love 

 so well do not occur in the county ; it is therefore only upon the 

 stonework and upon the brickwork of old buildings that these species 

 are represented. 



The first records of lichens are in Turner and Dillwyn's Botanist's 

 Guide, published in 1805, where fifteen species are enumerated. The 

 next list was by Mr. Edward Forster, to whom the county owes so much. 

 More recently the Rev. James M. Crombie has brought our knowledge 

 up to date. 1 



1 On the Lichen Flora of Epping Forest and the causes of its recent diminution,' Transactlmu 

 Eiiex Field Club, iv. 54, 1886. 



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