Meports and Proceedinys — Geological Society of London. 141 



The following commuuications were read : — 



1. '-The Matrix of the Suffolk Chalky Boiilder-clay." By the 

 Eev. Edwin Hill, M.A., F.G.S. 



The author has been examining with the microscope washed 

 residues from Boulder-clays. He is able to group together the 

 specimens from localities along a belt of country from Lowestoft 

 to Bury St. Edmunds, as containing granules of Secondary clays and 

 limestones. Other specimens contain granules which may be the 

 same kind decomposed, others granules of other kinds ; all these 

 lie outside the belt occupied by the group, though some are very 

 near it. The granules of the group, derived from Secondary rocks, 

 may all have come from the west. 



Certain peculiar round grains, found generally, except in the 

 extreme east and north, are also probably from Secondary rocks, 

 and they too point to a western origin. 



The clays of the group, though some occupy the coast-cliffs, 

 contain so little sand, that they cannot be supposed to have been 

 brought from the side of the sea, that is, from the east. 



All the residues have been examined for coal-dust. Though this 

 is contained in Grlacial clays along the eastern coast of England as 

 far south as the Wash, and probably farther, it is either altogether 

 absent from the group or present only on its eastern edge. It 

 appears to be absent from the clays which border the group on 

 the north. 



These results combined lead to the conclusion that the materials 

 of the matrix in the Suffolk Chalky Boulder-clay were not brought 

 from the east or north, but from inland ; and not from so far inland 

 as the Coalfields. Their sources therefore lie on a limited belt, 

 bordering the Boulder-clay area. 



With this agrees the evidence of the included boulders as a whole. 



2. " On the Eelation of certain Breccias to the Physical Geography 

 of their Age." By Prof. T. G. Bonney, D.Sc, LL.D., F.E.S., F.G.S. 



The author has endeavoured in this paper to collect from published 

 accounts and his own observations the evidence which certain 

 well-known and important beds of breccia afford as to the physical 

 conditions prevalent when they were formed. First come sketches 

 of the principal breccias in the Eothliegende, the brockrams of the 

 North-West of England and similar deposits in Armagh, the breccia- 

 beds of the Midlands and of Devon, and those of the Thiiringerwald. 

 The fragments in these vary fx'om angular to subangular, are some- 

 times interstratified with beds of finer material, sometimes are 

 themselves slightly stratified. They form marginal fringes to old 

 land-masses, from which we may. with more or less certainty, infer 

 them to have been derived, and are sometimes found to extend 

 outward from them, wedge-fashion, for a few miles. They appear, 

 for reasons given, to have been the products of bare rocky hill-slopes, 

 rather than of mountain torrents. Floating ice has been suggested 

 as a means of transport, though the idea that the Clent and Enville 

 breccias indicate the former existence of glaciers is not now generally 



