-1 
— 
OF A CAMBRIDGESHIRE WOODLAND, р 
to about 14 per cent. т July. Correlated with this dryness is the greater 
rapidity with which the soil warms up in the spring despite its paler colour, 
These features, combined with the physical and chemical characters of this 
soil, produce an entirely different type of vegetation from that on the 
caleareous clay. The following plants, so characteristic of that soil, are quite 
absent here *:— 
Viola hirta. Ligustrum vulgare. 
V. sylvestris. Orchis mascula. 
IH ypericum hirsutun. Habenaria virescens. 
Euonymus europeus. Listera ovata. 
Cornus sanguinea. Arum maculatum. 
Viburnum 2 spp. (urea remota, 
Cumpanula Trachelium. C. glauca. 
Primula elatior. | C. pallescens. 
The ground flora can be divided into two well-marked societies, a Pteris 
aquilina-IHoleus mollis Soe. and a /Joleus mollis Soc, without Pteris. 
Г. Pteris aquilina- Holeus mollis Society T. 
This society occupies the largest part of the loam area, The dominant 
plant in the full summer is Pteris aquilind, which forms a thick growth, 
rising to 3-5 ft. Моих mollis is dominant in the carly summer, The 
principal associates are :— 
Anemone nemorosa ......... а Scabiosa Succisa ............ о-1а 
Viola Riviniana ...........: о Primula vulgaris............ а 
Rubus macrophyllus ...... о Carew pilulifera ............ 0 
Potentilla erecta ............ 0 C, leporina уд... r 
P. sterilis д. о Polytrichum gracile ...... а 
Fragaria vesea нь. о Catharinea undulata ...... о 
Lonicera Periclymenum ... | Мтит undulatum ......... 0 
The principal perennial species are Anemone nemorosa and Primula vulgaris, 
as, unlike the society described by Woodhead t for oak woods in Yorkshire, 
Scilla nonseripta is here absent. About June olcus mollis reaches Из full 
development, while later Pteris ашпа with its fully expanded. fronds 
crowds and shades out most other species, and is solely and completely 
dominant. The only plants able to withstand it are strong-growing species 
such as Rubi, e. g. №. macrophyllus and R. silvaticus, and Scabiosa Succisa in 
more open parts. Except for Polytrichum gracile, which forms large pure 
patches, mosses are not very abundant in this society. 
* (f. Moss, 1907, р. 54. T Cf. Woodhead, 1906, p. 343. 
