218 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



The Coniston grits (No. 3) are magnificently brought out in the 

 great precipice called Colm Scar, and are of far greater thickness 

 than the flags ; and near their eastern end they are traversed by a 

 dyke composed chiefly, like many others in the neighbouring moun- 

 tains, of flesh-coloured felspar and black mica. 



But are the Coniston grits the exact equivalents of the rocks, which 

 m North Wales and Shropshire, &c., are represented, on the Go- 

 vernment Map, under one colour, as Caradoc sandstone ? To answer 

 this question fully wovdd require such a series of fossils as no one has 

 yet discovered, or perhaps ever will discover, in these hard sterile 

 grits. When I gave notice of this paper, I hoped, before it was read, 

 to have before me the last result of John Ruthven's labours. Un- 

 fortunately I have not yet received from him a single specimen, be- 

 yond those we collected together during a single day's labour on the 

 section just described. I may, however, express my full conviction that 

 the question implied m the title of this communication cannot be 

 settled by an appeal to the Coniston grits, but must have its final 

 answer determined by the more complete CAddence exhibited in the 

 more perfect sections of Wales and Shropshire, which gave to Sir 

 R. I. Murchison the base and superstructure of his " Silurian 

 System." 



Deeply do I lament that inevitable engagements prevented me, 

 during the summer months, from undertaking a joint labour with 

 Professor M'Coy, which I had long thought of, and believed it pos- 

 sible to complete in four or five weeks ; viz. of examining some of the 

 best sections through certain groups of strata which have hitherto 

 been described as Caradoc sandstone ; and, as such, are represented 

 by one colour in the beautiful published sheets of the Government 

 Survey, as well as in the Maps and Sketches that accompany Professor 

 Phillips's Memoir*. We could not begin our task before Tuesday 

 the 2 1st of September, and on the Monday following we were re- 

 luctantly compelled to abandon our task. We did, however, examine 

 the so-called Caradoc sandstone of May Hill, and the corresponding 

 deposits on the west flank of the Malverns, in perhaps sufiicient de- 

 tail for our express purpose ; and we bestowed some labour on the 

 well-known Horderley section, the upper beds of which were, how- 

 ever, concealed by the swollen state of the river Onny. Our attempt 

 on the Soudley section was almost entirely defeated. 



Had the sections been previously unknown to us, it would have 

 been utterly impossible to make, in so short a time, any approach to 

 their true interpretation ; but we had only to examine sections which 

 had been already described in ample detail ; and we confined our 

 inquiries to one simple question ; viz. whether the so-called Caradoc 

 group might not be naturally subdivided into two or more distinct 

 groups in conformity with the indications of the fossils ? 



May Hill. — Of the beautiful Silurian sections, those which cut 

 through the Woolhope elevation, and those which connect the coal- 

 field of the Forest of Dean with the sandstone axis of May Hill, are 

 perhaps the most clear and instructive. It would be idle for me to 

 * Memoirs of the Geological Survey of Great Britain, vol. ii. part i. 



