134: Geological Society. PROCEEDINGS OF LEARNED SOCIEITIES. GEOLOGICAL SOCIETY. March 14th, 1917.— Dr. A. Smith Woodward, F.R.S., Vice-President, in the Chair. Tlie following communication was read : — ' The Carboniferous Limestone bordering the Leicestershire Coalfield.' By Leonard Miles Parsons, D.I.C., B.Sc, F.G.S. The inliers of Carboniferous Limestone situated along the northern border of the Leicestershire Coalfield crop out in two well-defined series : — a Western series composed of almost hori-zontal beds exposed by stream-erosion, and an Eastern series in ■which the limestone is highly inclined and complicated by faulting. The thinly-bedded limestones, shales, and dolomites of the W^estern inliei-s are of a slightly-higher horizon than that of the upj^ermost beds of the more massive dolomites seen at Breedon and Breedon Cloud farther eastwards. In no part of the distinct is the base of the Carboniferous seen, although borings have shown that the limestone rests upon pre-Cambrian rocks in the neighbourhood of Charnwood Forest. The dolomites of the area yield evidence of two distinct periods of dolomitization — one pre-Triassic, the other subsequent to the Trias. During the former period the bulk of the rock was" dolomitized. The fauna of the limestones and dolomites indicates the presence of palseontological horizons ranging fi'om D^ to Dj^I^s inclusive. The D, portion of the sequence, consisting of thickly-bedded dolomites without chert, contains a fauna similar to that of the Caldon-Low facies of the south-western part of the Main Midland Province, the. rare species Productus humerosus being found at Breedon and Breedon Cloud. L'nlike the rocks of the D, subzone of Derbyshire, the corre-sponding beds in Leieestershii'e contain no igneous rocks equivalent to the ' Toadstones.' Higher dolomites with chert, equivalent to the cherty limestones of Derby shii-e, yield a D^ fauna, which somewhat resembles that of the localized development of the LonsdaJeia Subzone in the south-western part of the Midland area, in the region of Waterhouses. A typical D, development is not present in Leicestershire, although the upper barren dolomites of Ticknall may represent part of the Cyathaxonia Subzone of other districts. The Pendleside Beds are poorly represented by about 30 feet of blue shales, which are succeeded confoniiablv bv the Millstone Grit.
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