Reports and Proceedings — Geological Society of London. 375 



Dall." The author describes the specific characters in detail, but 

 fails to point out those which should mark the proposed genus from 

 its nearest allies. 



A new species of. Bhynchonella is founded on specimens showing 

 casts of the interior, and a new species of Gypidia is described. 

 Several new species of Platyceras, a new genus of corals, Bucano- 

 phyllum, and new species of Strombodes and Labecliia are introduced 

 and figured. Finally a new genus of Foraminifera named Moellerina 

 is based on some minute orbicular bodies with spiral ridges on the 

 outer surface. It seems to have escaped the notice of the author that 

 these bodies have been already described and figured by Professor 

 Dawson, as Saccammina (Calcisphcera) Eriana, and that they were 

 previously mentioned by Prof. Meek as probably the fruits of Chara. 



Ze-IEIFOIEeTS -&.JSTJD IFieOaiEIEIDHNr^S. 



Geological Society of London. 



I.— June 23, 1886.— Prof. J. W. Judd, F.E.S., President, in the 

 Chair. — The following communications were read : 



1. " On some Perched Blocks and associated Phenomena." By 

 Prof. T. McKenny Hughes, M.A., F.G.S. 



The author described certain groups of boulders which occurred 

 on pedestals of limestone rising from 3 to 1 8 inches above the level 

 of the surrounding rock. The surfaces of these pedestals were 

 striated in the direction of the main ice-flow of the district, while 

 the surrounding lower rock in no case bore traces of glaciation, but 

 showed what is known as a weathered surface. 



He inferred that the pedestals were portions of the rock protected 

 by the overhanging boulder from the down-pouring rain, which had 

 removed the surrounding exposed parts of the surface. When the 

 pedestals attained a certain height relatively to the surrounding rock, 

 the rain would beat in under the boulder, and thus there was a 

 natural limit to their possible height. 



He referred to the action of vegetation in assisting the decompo- 

 sition of the limestone, and considered that there were so many 

 causes of different rates of waste and so many sources of error, that 

 he distrusted any numerical estimate of the time during which the 

 surrounding limestone had been exposed to denudation. 



Considering the mode of transport of the boulders, he thought that 

 they could not have been carried by marine currents and coast-ice, 

 as they had all travelled, in the direction of the furrows on the rock 

 below them, from the parent rock on the north. Moreover, marine 

 currents would have destroyed the glaciation of the rock and filled 

 the hollows with debris. 



Furthermore, the boulders and stria? are found in the same district 

 at such very different levels and in such positions as to preclude the 

 possibility of their being due to icebergs. 



Nor could the boulders represent the remainder of a mass of drift 

 which had been removed by denudation, for the following reasons: — 



