134 SCIENTIFIC SURVEY OF BLACKPOOL AND DISTRICT 



The Millstone Grit Series is but feebly developed around the Lake District, 

 and the only rocks that can with confidence be referred to this series are the 

 shales and sandstones of the zone of Gastrioceras cumbriense. Zones R and H 

 appear to be absent, though E may be represented by the upper part of the 

 limestone measures. 



The Coal Measures succeed the Millstone Grit conformably, but with these 

 rocks we are not here concerned. Earth-movements, begun during the time 

 of the Coal Measures, resulted in upheaval before the onset of the Permian. 



New Red Sandstone and later rocks. 



Rocks of Permo-Triassic age bordering the Lakeland present several 

 interesting features pointing to unsettled conditions during the earlier part of 

 this period. Beginning with a breccia known as the Lower Brockram, these 

 rocks in Edenside pass upwards by way of the Penrith Sandstone, with its 

 Upper Brockram, into the Hilton Plant Beds, Magnesian Limestone, St. Bees 

 Shales, St. Bees and Kirklinton Sandstones, which are succeeded by the 

 Stanwix Shales. The Penrith Sandstone dies out to west and south, and 

 brockram is absent in many places, but in parts of West Cumberland replaces 

 Magnesian Limestone and St. Bees Shales. Magnesian Limestone is again 

 present in Furness. Gypsum deposits occur in the St. Bees Shales of 

 Cumberland and salt in the representatives of the Stanwix Shales in Walney 

 Island. The last-named shales are the youngest solid rocks intimately 

 associated with Lakeland. Others, of which there is a remnant of the Lias 

 near Carlisle, were probably deposited but later removed by the denudation 

 which followed the dome-like uplift of the district during Tertiary times. 

 This uplift gave rise to the radial drainage that persists to the present day 

 and accounts for the ring-like distribution of the Carboniferous and New Red 

 Sandstone around a core of older rocks. 



Space precludes giving an account of the Glacial deposits, though erratics 

 from the Lake District are common in the boulder clay of Blackpool 



XXI. 



THE BOTANY OF THE LAKE DISTRICT 



BY 



W. H. PEARSALL, D.Sc. 



TOPOGRAPHICALLY the Lake District may be held to include all the region 

 north of Morecambe Bay, west of the London, Midland and Scottish main 

 line, and south of a line drawn from Penrith to Maryport. Botanically, 

 however, this region contains examples of almost every typical British plant 

 community and it is much too varied to deal with in a limited space. It is 

 better, therefore, to consider merely the main botanical features of the central 

 mass of slatey rocks, since this includes all the characteristic Lakeland valleys. 



