THE PARISH OF HALIFAX. xiii. 



the moor edges, as Woodhouse Scar, Greetland Edge, the 

 Ladstone, &c. 



The sandstones, shales, clays and thin coal-beds of the 

 Lower Coal Measures occupy the rest of the parish, their 



western boundary being marked by the line of 

 Coal the escarpment from Swill Hill on the north, 



Measures. along the Ogden and Hebble streams to Elland, 



and by the Ainleys to Stainland in the south. 

 As these measures are capped by the sandstone known as 

 Elland Flag, they produce but little botanical difference, though 

 the shales are somewhat prominent on the valley slopes, as in 

 Shibden, Sun Wood and Elland Park Wood. 



The entire absence of igneous, slate or limestone rocks in 

 the area at once limits the number of plants, and simplifies any 

 examination of their distribution. As far as the rocks themselves 

 have any influence, there is hardly anything to prevent a species 

 from occurring in one part of the parish rather than another. 

 As will be shown later the altitude has much greater effect. The 

 grit rock is absorbent and porous but retains moisture. The 

 shales and clays are impervious and wet ; so that the whole 

 flora is composed of moisture-loving plants, or such as are in- 

 different. This is exemplified in the wealth of ferns and 

 mosses in the cloughs ; but at present the environment of the 

 plants, rather than the flora itself is under consideration. 



The soils, naturally therefore, do not offer greater variety 

 than the rocks. The prevailing type is a dark, sandy, heavy 



soil, always shallow, and holding a large amount 

 Soils. of moisture. Over the shales, chiefly on the 



Yoredale and Coal Measures, it becomes more 

 argillaceous, and therefore wetter and colder, but the shales 

 are more friable than clay, and there is very little stiff clay 

 soil. There is also only a small extent of alluvial soil : small 

 tracts of holme land occur near Mytholmroyd and Copley, but 

 the river only forms a flat valley bottom of any width in the 

 last mile or two between Elland and Brighouse, sufficient to 

 admit of a couple of crooks in its course. A light porous, sandy 

 soil is formed in small patches near the moors, or in the neigh- 

 bourhood of bare ground where the rain w r ashes together the 

 particles of sand crumbling from the exposed faces of rock. 

 There remains the peat, which attains its highest development 

 over grit rock, so much so that it is almost restricted to this 

 formation. Hence a large portion of the parish is covered with 

 peat to a varying depth. As deficient in organic constituents 



