Reports and Proceedings — Geological Society of London. 93 



I very mucli regret, since, as the author has taken me over all the sections 

 (as I believe) described in his paper — in most cases two or three times at 

 least — I should have liked to have expressed the opinions v?hich I have 

 independently formed. These are in full agreement with those set forth in his 

 paper, so far as I can gather from the abstract. In the Sudbury sections at 

 about 200 feet above O.D., a quite normal 'Chalky Boulder-clay' is seen 

 overlying well-stratified silts and sands, with occasional false-bedding. These 

 present every appearance of having been deposited under water, which was 

 moving very gently and steadily. Their stratification shows no disturbance as 

 it approaches the base of the Boulder-clay, and the latter does not in any way 

 scoop or dig into it ; but we find, not seldom, signs of a real, though rapid, 

 transition from the one to the other. 



"But, from about 180 to 100 feet O.D., that is more or less on the flanks of 

 the Stour Valley (which the Glemsford boring has shown to be pre-Glacial) — 

 sand, gravel, and Boulder-clay (normal) show great disturbance and strange 

 associations — masses of the last material occurring in the others, like large 

 irregular erratics. Their mutual relations are not suggestive of a ploughing-up 

 by the snout of a glacier (which, had it deposited the Boulder-clay, would by 

 this time have retreated from the district), but a downslipping of the older 

 materials and a mixture of them with coarser gravels of more local origin. 



" I may add that, sometimes in the author's company, sometimes with others, 

 I have seen this orderly succession of silt, sand (more or less gravelly), and 

 Boulder-clay, in other parts of the Eastern Counties, and not in them only. 

 Thus, while I am fully conscious of the difficulties presented by the hypothesis 

 of the subaqueous deposition of Boulder-clay, that which regards it as the 

 direct product of an ice-sheet seems to me to involve yet more serious difficulties, 

 at any rate in our Eastern Counties." 



2. "The Ordovician and Silurian E.ocks of the Kilbride I'eninsula 

 (County Mhto)." By Charles Irving Gardiner, M.A., F.G.S., and 

 Professor Sidney Hugh Reynolds, M.A., F.G.S. 



The Kilbride Peninsula includes thrive principal groups of rocks. 

 The northern and western part is, in the main, composed of igneous 

 rocks, contemporaneous and intrusive, of Arenig age ; the southern 

 and eastern part principally consists of Silurian rocks, but these are in 

 the south-eastern corner of the peninsula faulted against an area of 

 gneiss. The Arenig rocks resemble the Mount Partry Beds of the 

 Tourraakeady and Glensaul districts — in the fact that they include 

 cherts and shaly beds with Didymograptus extensus, and in the 

 presence of gritty tuffs and coarse breccias, the latter rocks showing 

 a magnificent development. . No coarse conglomerates, however, occur, 

 and no limestone breccias or other representatives of the Shangort 

 Beds of Tourmakeadj' and Glensaul, while Arenig sediments of all 

 kinds are very scarce. The most interesting feature of the Arenig 

 rocks is the great development of spilitic lavas, which are commonly 

 associated with cherts and often show good pillow-structure. Their 

 resemblance to tlie similar rock of the Girvan district is very close. 

 An enormous mass of felsite with large quartz-phenocrysts, and often 

 albite, as also pseudomorphs after rhombic pyroxene, occupies much of 

 the northern part of the peninsiila. There is no doubt that it, like the 

 similar masses of Tourmakeady and Glensaul, is of Arenig date. The 

 Silurian rocks consist principally of grits, sandstones, and calcareous 

 flags, and dip with t;reat regularity in directions varying from south 

 to east. The calcareous flags (Finny School Beds) are highly 

 fossiliferous, and have yielded over fifty species, principally of corals 

 and brachiopods, which prove the beds to be of Llandovery age. 



