432 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 22, 



plains, and tlie peat bogs at the foot of the Euganean Hills contain 

 the teeth of the horse, the boar, and a small animal alhed to the 

 beaver. 



This rapid sketch of our stratified rocks in the north of Italy is 

 intended to show how by the aid of fossils a suite of formations from 

 the mica slate to the most recent can be traced ; beds often geogra- 

 phically distant can be shown to be identical ; and some which are 

 identical in mineral composition can be proved to be distinct. 



With the aid of fossils I have marked the boundary of the trias, and 

 shown that in our Jurassic formation the lower and middle divisions 

 occur with traces of the upper. Next I have shown that our lower 

 cretaceous beds are divisible into 'Neocomian' and ' Albian,' and the 

 upper mto M. d'Orbigny's two divisions, 'Turonian' and ""Senonian.' 

 Our tertiaries, not having previously been accurately studied, had all 

 been confounded in one group, the Miocene. I have shown that they 

 are distinguishable into Eocene, Miocene, and Pliocene, and have sa- 

 tisfied myself that our great nummulitic formation is undoubtedly 

 Eocene. I doubt whether there are any secondary nummulites. In 

 a memoir on the cretaceous beds of Italy, I mentioned the occurrence 

 of traces of nummulites under the scaglia ; but I have since satisfied 

 myself that these lenticular bodies were broken shells rounded by 

 attrition. In the Alps I look upon nummulites as the most charac- 

 teristic fossil of the tertiary period, and I shall regard as tertiary any 

 beds wherein they shall be found to occur. 



3. On the Age and Position of the Limestone of Nash, near 

 Presteign, South Wales. By James Edward Davis, Esq., 

 F.G.S. 



The picturesque and very valuable mass of limestone, situated on 

 the borders of Wales, near the road leading from Presteign to New 

 Radnor, and overhanging the hamlet of Nash, is probably kno^vn by 

 name to most Silurian geologists, but I am not aware that it has 

 been carefully examined by any geological investigator since the pub- 

 lication of Sir Roderick Murchison's 'Silurian System.' The interest- 

 ing features of the neighbourhood of Presteign and Old Radnor 

 could not fail to attract the attention of that distinguished geologist, 

 who says of the Nash beds that there is not perhaps in Great Britain 

 a finer mass of altered and crystalline hmestone. 



After an examination of this district, the details of which are given 

 in the ' Silurian System,' Sir RoderickMurchison states this hmestone 

 to be identical in position and organic remains with that of Wenlock. 



In conformity with this opinion, and, indeed, following it, the 

 views of the structm'e of the smTounding district were framed and 

 shaped, as far as I am aware, by all who had any definite idea on the 

 subject, or took an interest in its investigation, but more particularly 

 by the Rev. T. T. Lewis of Aymestry, and myself. 



