152 Geological Society: — - 



They are much like some of the Lower Silurian flags in Wales, and 

 are in no degree more highly altered than the majority of those 

 rocks, especially in the more disturbed districts. About three miles to 

 the east of Glyn Laggan these beds die out, or at least are lost, and 

 the Lewisian rocks, fundamental gneiss, hornblende- schists, and 

 mica-schists, such as those described on the east of Loch Maree, 

 again come to the surface ; and the whole of the remainder of the 

 section consists of these last rocks, the great mountains Ben Pyn, 

 Mulart, and others being entirely made up of these rocks without a 

 vestige of the unaltered beds reappearing there. Of the gneiss, 

 hornblende-schists, and mica-schists which compose these moun- 

 tains, it need only be said that, on comparison with others from 

 Loch Maree, Gaerloch, &c, it is impossible to recognize any dif- 

 ference in them, the metamorphism being in each case identical in 

 character, and garnets and other crystals occur in them in equal 

 abundance. The strike of the beds at Ben Pyn he found also to be 

 almost identical with that of those on the west coast, the dip being 

 either to the N.E. or E., and seldom if ever south of that point. He 

 also found these rocks, and with a similar strike, in the low ground 

 in Glyn Docherty, near the road to Auchnasheen ; and there the 

 Silurian beds are seen resting un conformably upon them. Prom 

 this the author believes that the Cambrian and Silurian beds are 

 contained in a basin or depression formed of the older rocks, being, 

 however, now altered in their dip and position by slight faults and 

 some folding which has taken place since they were deposited. 



3. tl - On the Triassic Kocks of Normandy and their Environments." 

 By "W. A. E. Ussher, Esq., E.G.S. 



The author stated that his investigations were confined to the 

 provinces of Calvados and La Manche, more especially the latter. 

 Having briefly alluded to the physical areas of the Bocage and 

 Cotentin, he proceeded to show that whilst the Secondary rocks were 

 confined to the Cotentin, the presence of several Palaeozoic inliers 

 proved that they were of no great thickness. He then briefly 

 described several sections illustrative of observations made by him 

 in walking over the Triassic districts of Yalognes, Montebourg, and 

 Carentan, and of Bayeux in Calvados. The result arrived at (as 

 far as possible, despite the presence of drift concealing the Trias 

 almost everywhere) was that the Norm an Trias is composed of 

 gravels, sands and sandstones, and marls. The gravels replace and 

 give place to sand and sandstone ; but the position of the marls could 

 only be distinctly ascertained near Carentan, where they underlie 

 sandstones. The gravels and sands either directly underlie the 

 Infra-lias, or are separated from it by a thin bed of marl. The 

 Norman Trias can scarcely exceed 200 feet in thickness. 



The author then briefly enumerated the Palaeozoic rocks of the 

 Bocage, and summed up the results of his investigations in the 

 following conclusions : — 



Pirst, that the Triassic rocks of Normandy are the south-easterly 

 prolongation of the Triassic area of Somerset and Devon. 



