PROCEEDINGS OP THE GEOLOGICAL SOCIETY. 6j 



the whole Tertiary flora, if we wish to obtain the general picture of 

 a flora. These will constitute the following volume. 



In the elaboration and the discovery of the materials for this 

 next volume, Professor A. MeDge, who died in Danzig in January 

 1880, has an important share. The collection of inclusions in 

 Amber, his work, is now in the possession of the Naturforschende 

 Gesellschaft zu Danzig, as an inestimable treasure. But all that 

 relates to the Amber tree, some 1000 hand specimens and prepa- 

 rations, belongs to my collection. The figures on Taf. iv.-viii. 

 also show the types of the fossil Coniferae, which may serve for the 

 determination of fossil Coniferse in general and of the remains of 

 wood enclosed in Amber. Among them the type of the Araucariat 

 (our Araucarites) merits special mention, in remembrance of its 

 introduction by Witham into his classical memoir ' The Internal 

 Structure of Fossil Yegetals ' (Edinburgh, 1833), which will always 

 claim an honourable place in the history of phytopalaeontology. 

 • In conclusion, I introduce in my work an attempt to explain the 

 enigmatical fossilization of Amber, and the disappearance of the 

 trunks furnishing the Amber, which only remain to us in a few 

 fragments of 2-3 inches long in my possession. 



(Signed) Dr. Heinrich Robert Goppert. 



The following communications were read : — 



1. "On the Relation of the so-called '.Northampton Sand' of 

 North Oxfordshire to the Clypeus-Q-rit." By Edwin A. Walford, 

 Esq., F.G.S. 



2. "Results of Observations in 1882 on the Positions of 

 Boulders relatively to the Underlying and Surrounding Ground, in 

 North Wales and North-west Yorkshire ; with Remarks on the 

 Evidence they furnish of the Recency of the Close of the Glacial 

 Period." By D. Mackintosh, Esq., E.G.S. 



[Abstract.] 



The author began by showing how boulders may be regarded as 

 natural time-measurers by their protecting the rock-surface under- 

 neath from the action of rain, which, around the boulders, denudes 

 the surface, especially on the leeward and windward sides, where 

 hollows resulting from pluvio-torrential action may generally be 

 seen. He then described and explained the origin of the different 

 forms of supports under boulders, which graduate from flat surfaces 

 to pedestals of various forms, which he divided into appropriated 

 (or preexisting), and those acquired through the boulders protect- 

 ing the underlying rock from denudation. The author then de- 

 scribed the positions of boulders on the high and uninhabited 

 Eglwyseg limestone plateau near Llangollen, where it is certain 

 they had never been disturbed by man. There he found that the 

 average vertical extent of denudation by pluvial action around the 

 boulders, since their arrival, was not more than six inches. After 



