Flora of Hayes Common. 53 
composed of the Oldhaven beds ; the lowest part of West Wick- 
ham Common scarcely touches the chalk; and the Thanet sand 
and Woolwich beds, if present near Coney Hall, must be very 
thin, and are almost entirely concealed by rainwash from the 
slopes above. The Oldhaven beds consist mainly of round-pebble 
gravel, with some sand. The surface soil is peaty on the bare 
common, but near the roads and on the N. border it is loamy or 
sandy. The surface of the common is mostly dry; there are no 
running streams, and the only water to be found is in a few 
ponds, one by Coney Hall, one near the centre of the S.W. 
border, and one or two near the N.K. border. These are the 
only stations for aquatic plants. The EK. corner of the common 
near the road to Keston Mark is the wettest part of the common, 
the natural drainage tending in this direction ; and here several 
bog-loving plants are still found. On the common there are a 
number of gravel-pits, some still worked, others long disused and 
overgrown with turf and bushes ; others again are used as places 
of deposit for rubbish of various kinds. 
The vegetation on the common has suffered much during the 
_ recent dry summers from fires, a large portion of the §.E. part 
_ of the common having been burnt a year or two ago. This fire 
was so strong as to cross the roads, whereas generally even a 
footpath is sufficient to arrest the progress of a heath fire. After 
a fire the first vegetation to appear consists of mosses, especially 
Funaria hygrometrica and Ceratodon purpureus, together with the 
young shoots of strong growing plants, such as the gorse and 
bracken, the deep roots of which the fire has failed to reach. In 
@ year or two, when a little mould has formed, the burnt surface 
is taken possession of by certain plants which thrive in barren 
soils, such as Senecio sylvaticus, Aira flexuosa, Rumea Acetosella. 
____On the open parts of the common, as on peaty heaths gener- 
ally, the vegetation is made up of comparatively few species of 
_ plants—the gorse, the ling, and purple heath, and several species 
of grasses, especially Aira flexuosa, Festuca ovina, and Agrostis 
_ canina forming the bulk; there are also hawthorn trees dotted 
about, which afford harbour for the honeysuckle and brambles. 
Of the plants of wet and boggy ground which are still to be 
found on Hayes Common, may be mentioned the berry-bearing 
_ alder (Rhamnus Frangula), the marsh pennywort, Genista anglica, 
the cross-leaved heath, the creeping-jenny, the lesser skullcap, 
_ Salia repens and aurita, several rushes and sedges, and Nardus 
_ stricta. These, as already stated, are chiefly found in the low 
_ damp ground at the E. corner of Hayes Common. Old records 
‘quoted in Hanbury’s ‘ Flora of Kent’ name a number of other 
_ bog-loving plants as formerly found on Hayes Common, e.g. 
_ Hypericum elodes, Drosera rotundifolia, Wahlenbergia hederacea, 
i Menyanthes trifoliata, Narthecium Ossifragum, and Osmunda regalis; 
; 
hs 
