OF А CAMBRIDGESHIRE WOODLAND. 359 
Also present in considerable quantity are :— 
Ranunculus Ficaria о Stachys officinalis 
Viola Riviniana. о | Rumex тев. 
V. sylvestris o ss TN Orchis mascula 0. o 
Fragaria vesea 0. о—а | Habenaria virescens ......... r 
Rubus cesius (small plants) o Listera ovata... о 
Cnieus palustris |... ool о Luzula pilosa.. о 
Ajuga reptans о 
And locally small plants of :— 
Deschampsia eespitose .. . ] 
"M r 
Poa trivialis „н.а. 
Mosses * are fairly abundant in this society, especially :— 
Thuidium tamariscinum t.. а | Brachythecium rutabulum о 
Hiylocomium triquetrum ... a В. velutinum о 
Hypnum cupressiforme ... a | Mnium undulatum |, r 
(especially on trees). | 
The average light-value here for the summer months is 0°03-0°01, or even 
less. Owing to this small intensity the Spiræa does not flower except along 
the paths and in more open parts. In a few parts of this society the light is 
still further reduced, 0°01-0-005 ; here Spiræa is thinly scattered or absent 
locally. Anemone nemorosa, Primula elatior, and, locally, Seilla nonscripta 
form the principal covering. 
These are species in which the active period comes on early, before the full 
foliage is out on the trees and shrubs ; in this part in summer the ground may 
he almost bare, except for the Oxlip leaves and the yellow dying leaves of 
Anemone and Scilla with the mosses. 
The normal shade Spiræa Society has a high water-content for the soil. 
The annual mean is 47 per cent., with a range from 90-33 рег cent. It very 
exceptionally rises above 60 per cent., except when the water-table rises above 
the surface ; the summer average is about 40 per cent. The very shaded 
parts where Anemone nemorosa becomes prominent are rather drier, averaging 
35 per cent. in the summer. 
А quadrat { was laid down in a typical part of this society to show, among 
other things, the seasonal changes or aspects. In spring Spirea is not very 
impor! tant. The dominating plants are Primula elatior, Anemone, and Viola 
Riviniana with V. sylvestris. Later in the year the Spirwa forms an almost pure 
covering, with Oxlip tufts at intervals, Mosses become dominant in winter, 
* Watson, 1909. t The nomenclature is that of Dixon & Jameson's Handbook, ed. 2, 1904. 
t Clements, 1905, p. 162. 
LINN. JOURN.—BOTANY, VOL, XL. 2с 
