282 Geological Society : — 



Block C extends from the above to the point where the Bagshots 

 are first cut through to the level of the line, and the hollow filled 

 up with Plateau-gravel — 165 yards. 



Block D exhibits the relations of the Bagshots to the Plateau- 

 gravel, where the latter is most fully developed — 247 yards. 



Details of Block A. — This portion of the section rises from zero 

 to 12 or 14 feet ; the first bed which becomes visible is the " Top 

 Sand," and on advancing further westward portions of a peculiar 

 mixture of gravel and lumps of brown clay form the sides and floor 

 of the cutting. This is evidently a disturbed series, and has pecu- 

 liar relations with a mass of yellow sand, mainly false-bedded, which 

 is 70 yards long, and from 12 to 14 feet high at the west end. The 

 London Clay in situ rises very suddenly beyond this. Reasons were 

 given for supposing this sand to be a superficial deposit against a 

 steeply eroded surface of London Clay. 



Details of Block B. — The London Clay of this block has yielded 

 no fossils, nor are any Septaria visible. The bedding is difficult to 

 distinguish, but recent weathering has made it more plain. This 

 seems to establish a very slight dip towards the west. The surface 

 of the London Clay is undulating, and it is overlain by from 6 to 7 feet 

 of Piateau-gravel. 



Details of Block C. — In this block, where the cutting has a depth 

 of about 24 feet throughout, occurs the junction of the Lower Bag- 

 shots with the London Clay, and this is apparently an unconformable 

 one. Both the lithology and the stratigraphy favour this view. 

 Nothing in the nature of a lithological passage exists. The lowest 

 bed of the Bagshots here is remarkably clear sand full of false- 

 bedding, and is succeeded by an argillaceous series, also somewhat 

 sandy. It was suggested that this latter might be the equivalent 

 of the " Pamsdell Clay." 



Details of Block D. — Here the Plateau-gravel attains its maxi- 

 mum thickness, since the Bagshots are cut through to the level of 

 the line in three places — depth of cutting from 24 to 27 feet, — thus 

 affording a fine opportunity for the study of this peculiar deposit. 

 Three horizons were roughly made out, or, rather, three varieties oc- 

 curring one above the other. Beyond the limits of the section there 

 is more distinct evidence of at least two groups in these Plateau- 

 gravels. No materials from the northern drift are found. 



Other sections in the superficial beds were noticed, and more 

 especially one about the 180-feet line on the north slope of St. 

 George's Hill, where the contortions are of considerable interest. 



January 27.— Prof. T. G. Bonney, D.Sc, LL.D., F.K.S., President, 

 in the Chair. 



The following communications were read : — 



1. "On the Fossil Mammalia of Maragha, in North-western 

 Persia." By P. Lydekker, Esq., B.A., F.G.S., &c. 



2. " On the Pliocene of Maragha, Persia, and its resemblance to 

 that of Pikermi, in Greece ; on Fossil Elephant-remains of Caucasia 

 and Persia; and on the results of a Monograph of the Fossil Ele- 

 phants of Germany and Italy." By Dr. H. Pohlig. 



