420 Geological Society. 



(Middle Devonian) and trougked in them by faulted synclines ; 

 Morte slates passing into Ilt'racombe slates (overlying Hangman 

 grits) near Cutcombe; Hangman grits evidently faulted against 

 Foreland grits, as no representative of the Lynton beds is present 

 between Oaktrow and Timberscombe. 



In traverse 2, the fault between the Hangman and Foreland 

 grits is proved by the presence of the Lynton beds in the valley west 

 of Luceot Hill and their conformable infraposition to the Hangman 

 series, and abrupt termination by fault against the Foreland grits 

 of Porlock and Oare Hills. At Oare a patch of schist of the Lynton 

 zone was noticed resting on the Foreland grits on the north side of 

 the fault. 



The 3rd traverse, in the Tone valley, gave the following succession 

 of beds : — Culm-measures on Pilton beds ; Pilton beds with grits, 

 much flexured, on Olive slates with Lingula and grits with Cucul- 

 Icea, conformably overlying Pickwell-Down grits, which make a con- 

 formable junction (following the feature) with the underlying 

 quartziferous slates of the Morte series (Middle Devonian) ; the 

 latter were observed between Huish Champnower and Clatworthy ; 

 but as the Middle Devonian slates appear to extend considerably 

 northward in the Brendons, they were not traversed beyond Clat- 

 worthy. 



The 4th traverse, from West Quantockshead to Cannington Park, 

 proved the composition of the Qnantocks along that line to be grits, 

 in places associated with schistose shales, apparently belonging to 

 the Hangman series (Middle Devonian) ; whilst the Palaeozoic 

 inliers, in the Triassic area of Bridgewater, are unlike the Quantock 

 rocks in character. The limestones of Asholt and Hollwell, asso- 

 ciated with slates of the llfracombe series, are very similar to varie- 

 ties of the South-Devon limestone, and are quite unlike the lime- 

 stone of Cannington Park. 



3. "The Whin Sill of Teesdale as an Assimilator of the sur- 

 rounding Beds." By C. T. Clough, Esq., F.O.S. 



Owing to the general absence of mechanical disturbance, the 

 author is of opinion that " the whin consists in part of altered 

 sedimentary beds, that it partly represents beds which were once 

 in the position it now occupies, that it did not make room for itself 

 simply by thrusting aside these beds, but also by incorporating them 

 into itself." He proceeds to describe sections at Caldron Snout, 

 Cronkley Fell, Noon Hill, <fcc, which seem to him inexplicable on any 

 other theory. The author discusses objections on chemical grounds, 

 holding that the general uniformity in chemical composition of the 

 Whin may be explained by supposing the absorbed beds to have 

 permeated a large mass of the Whin, as an alloy does melted metal. 

 He thinks the explanation may be extended to other intrusive 

 masses. 



4. " On the Silurian Bocks of the Valley of the Clwyd." By 

 Prof. T. M'Kenny Hughes, M.A., F.G.S. 



The author gives a preliminary sketch of the Silurian rocks of 

 the southern and western part of the Clwyd valley. He describes 



