The Woodlands of England. 14.1 
dioica), columbine (Aquilegia vulgaris ), meadow-sweet (Spiraa 
Ultnaria), wood-avens (Geutn rivaled, yellow dead-nettle Lamium 
Galeobdolon), woodruff Aspcrula odorata\ and Valeriana 
Mikanii, are frequently abundant. 
In situations of ordinary dampness, extensive sheets of dog's 
mercury ( Mercurialis pc re tin is) occur ; and. in certain localities, 
this plant and the moschatel ( Adoxa Mosehatellina ) form an 
interesting “ complementary ” society. 1 
The dry parts of the ashwood are characterised by stretches 
of ground ivy ( Xepeta hedt aces). Taller herbs occur, especial ly 
Hypcricum hirsutuin, Urtica dioica, and TeucriuScorotionia, 
forming close herbaceous thickets in summer. The last named 
species belongs to an interesting class which occurs in some of the 
drier woods of the oak and birch series, as well as in the ashwoods 
J 
but is absent from the oak-ashwoods. Locally, the ltty-of-the- 
valley ( Convallaria majalis ) and the stone-bramble Rubus 
saxa:il:s) form fairly extensive ground societies : and in these the 
nodding melic-grass (Melica ns) sometimes occurs. 
The very driest parts of the ashwood occur on the rocky 
knolls. Here the soil is extremely shallow, and in places the bare 
rock protrudes. Trees and shrubs are absent; and the absence of 
shade allows of the growth of saxicolous lichens and bryophytes, 
such ephemera’s as Draba and Sa.r./ ng.: :ndactyl::cs, and 
such dwa:: perennials as Sedum acre and Thy in: S. rylltint. 
Such a community does not. except in a topographical sense, belong 
to a woodland association at all. Screes and cliffs are also found 
within the ashwoods: but these in time become clothed with trees 
and shrubs; and it is possible, by observing several such localities, 
to construct a series of plant associations which illustrate a 
historical natural succession from the bare screes or cliffs to the 
ashwood. 
Ground societies of Air a desuosa, Hoicus > noil is. and Vac- 
c.”.:.. : Mvriillus , so characteristic of the oak and birch series, are 
totally absent from woods of the beech and ash series. 
The following species are confined to the more northern woods, 
and are either found only in ashwoods or are more abundant in them 
than in oakwoods: — Mclica nutans, Festnca sylvatica, HorJcu>n 
sylvaticum. Cares orntthopo<Li. Helleborine atro-rubens, Troliius 
europs:is, Act.cn spicaia, Geranimn sylvatic: :. Pole nonium 
r Sec Woodhead. l.c., p. 545. 
