276 
NOTES ON THE ECOLOGY OF LICHENS, WITH 
SPECIAL REFERENCE TO EPPING FOREST. 
By R. Paulson, F.L.S. 
With Five Illustrations, 
[Read 23 rd January 1918.] 
A FTER three years and a half of a most disastrous war, 
which has brought in its tram a great shortage of food., 
everybody realises the national importance of an exact 
knowledge of the relation of plant to soil and environment. 
Questions respecting the reclaiming of saltings, the breaking 
up of pasture-land by the plough, and the re-afforestation 
of large tracts are all claiming solution. Ecology, one of the 
newest branches of biological science, has something to offer 
in the way of guidance as the result of various experimental 
methods that were being worked out in times of peace. 
I am aware that my subject touches upon the fringe only 
of that of Forestry ; but that of the Ecology of Fungi, with 
which it is so closely related, is of the utmost importance. It 
is only with a fuller knowledge of the several groups of crypto¬ 
gams that we can come to a more exact understanding of the 
various plant-associations of the Forest. 
Turning for a moment from the purely-utilitarian aspect 
of what has just been said, we could wish to add the words 
moss, lichen, and fungus after the plants enumerated in the 
following paragraph by E. N. Buxton 1 :— 
“ The peculiarities of the various woods which I have 
endeavoured to indicate are not confined to the larger growths, 
but extend to that which covers the surface grass, heather, 
brake-fem, gorse, broom, or black-thorn, according to the soil 
and aspect. From the above remarks, it will be seen what a 
charming diversity we have inherited—incomparably more 
interesting than a wood which, however beautiful, is all of one 
pattern.” 
Five 3'ears have elapsed since the second and concluding 
part of the “ Report on the Lichens of Epping Forest,” by 
Paulson and Thompson, was placed before the Essex Field Club 2 . 
In that report, a small section was given to habitats and plant- 
associations as they exist in the Forest area. Since then, I 
have occupied some of my spare time in comparing the lichen- 
flora of the Forest with that ol other woods and heaths in counties 
1 F.fpiiui Forest, p.157 (1905). 
a Essex Naturalist, xvii , pp. 90-105 (1914). 
