TRANSACTIONS OF SECTION C.—PRESIDENTIAL ADDRESS. 453 
Section C.—GHOLOGY. 
PRESIDENT OF THE SEcTION.—PrRoressor HE. J. Garwoop, M.A. 
THURSDAY, SEPTEMBER 11. 
The President delivered the following Address :— 
On the last occasion when members of the British Association met in Birming- 
ham, in 1886, this Section was under the able presidency of my friend Professor 
T. G. Bonney, who at that time occupied the chair of Geology in University 
College, London. Fifteen years iater I succeeded him on his retirement from 
that post, and to-day I succeed him as President of this Section, at the fifth 
meeting of the Association at Birmingham; once more I feel the same diffidence 
in following him in Birmingham as I did in London. 
In his Address in 1886 Professor Bonney discussed the ‘ Application of 
Microscopic Analysis to Discovering the Physical Geography of Bygone Ages.’ 
Strangely enough, this title might apply almost equally well to the subject 
of my Address to-day ; but whereas Professor Bonney employed for his purpose 
the evidence obtained from observations on mechanical sediments, I propose 
to deal with certain organically formed deposits with the same object. 
More than twenty years ago, whilst engaged in the study of the Lower 
Carboniferous rocks of Westmorland, I noticed the occurrence of certain small 
concretionary nodules of very compact texture, in the dolomites near the base 
of the succession in the neighbourhood of Shap. 
Shortly afterwards, when examining the Bernician rocks of Northumberland, 
I again met with similar compact nodular structures. It was obvious, however, 
even at that time, that the Northumberland specimens occurred here at a much 
higher horizon than those which I had observed in Westmorland. 
More recently, whilst studying the lithological characters of the Lower 
Carboniferous rocks of the North of England and the Border country, I have 
been still further impressed by the abundance of these nodular structures at 
several horizons, and the large tracts of country over which they extend. An 
examination of these nodules in thin sections showed their obvious organic 
character, and I was at first inclined to refer them to the Stromatoporoids. 
Dr. G. J. Hinde, who was kind enough to examine my specimens from the Shap 
district, reported, however, that they were probably not Stromatoporoids, but 
Caleareous Alge, and referred me to the descriptions of Solenopora published 
by the late Professor Nicholson and Dr. Brown. 
Since then I have examined a large number of nodules collected from 
different horizons in the Lower Carboniferous rocks of Britain and Belgium; 
and the examination has convinced me that the remains of Calcareous Algze 
play a very much more important part in the formation of these rocks than has 
hitherto been generally realised. 
The majority of geologists in this country have been slow to recognise the 
