875 
Woods of North-East Kent. 
turn, L., occurs sparingly only on the deepest parts of the Clay. In addition 
to the above-mentioned plants, a considerable number of other species occur; 
Stereodon cupressiforniis (L.), Brid., Hypnum rutabulum , L., and Thuidiurn 
tamariscifolium (Neck.), Lindb., are frequently found. 
In the eastern part of the wood the age of the coppice over the whole 
extent of the Clay nowhere exceeds three years, and here a definite 
zonation of the vegetation can be found in consequence of the above de¬ 
scribed distribution. The following zones can be distinguished :— 
I. The soil is less than two feet in depth. The flora is in many 
respects similar to that of the Chalk, although several plants constantly 
found on the latter formation, such as Reseda lute a > Origanum vulgare , 
and Helianthemum Chamaecistus , do not appear. Teucrium Scorodonia is 
abundant, and Hypericum perforatum is frequent. Large patches of 
Poly trichum juniperinum are found, and Cladonia pyxidata occurs spar¬ 
ingly. 
II. Depth of soil from % to 3 feet. Teucrium Scorodonia is less abun¬ 
dant, and there is a considerable increase in the amount of Hypericum 
perforatum. Holcus mollis , Holcus lanatus , and Anthoxanthum odoratum 
occur sparingly. Polytrichum attenuatum replaces P oly trichum juniperinum 
and Mnium hornum is frequently found. 
III. Soil 3-4 feet in depth. The Grasses ( Holcus mollis , Holcus lanatus , 
and Anthoxanthum odoratum ) are abundant, giving a characteristic appear¬ 
ance to the flora. Hypericum perforatum is also abundant. Car dims palustris 
and Sanicula europaea are frequently found. Both species of Poly trichum 
are absent, and are replaced by Catharinea undulata and Mnium hornum. 
IV. Soil 4-6 feet in depth. Carduuspalustris is abundant, while there 
is a decrease of the Grasses and of Hypericum perforatum. Adoxa Mos- 
chatellina ) absent from the shallower soils, is found, while Sanicula europaea 
shows a considerable increase. Catharinea undidata is abundant, while 
Mnium hornum has disappeared. 
V. Soil over 6 feet in depth. Car dims palustris is very abundant, the 
plants being tall and luxuriant. Sanicula europaea and Adoxa Moschatel- 
lina are also abundant, Rumex obtusifolius, Rumex sanguineus , Polygonum 
aviculare y and Polygonum Persicaria are sparingly present. Mnium undu- 
latum is found in addition to Catharinea undidata. 
Analyses of soil from the different zones are not yet available, and until 
these are obtained no definite statements as to the cause of the above dis¬ 
tribution can be made. Meanwhile it may be suggested that the zonation 
is largely influenced by the variations in the water content. In the shallow 
soils the drainage through the easily permeable chalk will be rapid, and the 
water content correspondingly small, but, with the increasing thickness 
of the clay, the drainage will be slower and the percentage of water retained 
by the soil will be greater. The lifting power also will be increased. 
