854 MR. T. W, WOODHEAD ON THE 
This suggested a more extended examination of soils. The 
whole area under consideration lies on the Lower Carboniferous 
formations. Glacial deposits are entirely absent, and, except 
for deposits of peat to be mentioned below, the soils owe their 
origin chiefly to the direct denudation of the rocks. Lees (55) 
has given an interesting account of the “ Lithology” of West 
Yorkshire, giving lists of species characterizing the several soils. 
In this he follows Thurman (96) and Baker (2), and finds that 
the soils exert a profound influence on the flora, due largely to 
their * mechanical" properties and to a much less extent to their 
chemical composition. Much has of late been written on this 
subject, an interesting summary of which has recently been 
given by Solms-Laubach (90). In the present study the works 
of Roux (82) and Hall (43) have been found very helpful. 
Numerous analyses have been made of the soils in the different 
areas treated of in this paper, but the results are as yet too 
incomplete to be satisfactorily dealt with here, but they indicate 
that physical factors, especially those affecting available water, 
here play a more important part than the chemical, and the 
question of the influence of lime on vegetation is excluded by 
the total absence of these deposits in the district. 
On the maps (figs. 9 & 10) the various features considered are 
shown only in the areas not under cultivation, from which it is 
clearly seen that while the distribution of certain species is 
influenced profoundly by the dominant tree, other factors are 
strikingly brought out. The extensive development of Pteris, 
ericaceous plants, and other xerophytes to the west is in remark- 
able contrast to their relative scarcity towards the east, where, 
however, they were somewhat better developed formerly than 
now, their reduction being due largely to cultivation. 
The vegetation of this district will be seen to consist of 3 zones, 
using the term zone in the sense applied by Flahault (30), to 
indicate the successive stages of vegetation from the base to the 
summit of a mountain :— 
(1) Tue Moss Moor, which is high, wet, cold, and covered by 
deep deposits of peat, the dominant plants being cotton-grasses 
(Eriophorum vaginatum and E. angustifolium), and the more 
elevated and drier ridges being clothed with Vaccinium Myrtillus, 
Empetrum, &c. Bracken-covered slopes, with xerophytic asso- 
ciates, connect this zone with No. 2. 
(2) Mittstone-Grit PrATEAU.—AÀn ericaceous zone of medium 
