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On the Fresh-water Limestone of Burdichouse in the neighbour- 
hood of Edinburgh, belonging to the Carboniferous Group of 
Rocks. With Supplementary Notes on other Fresh-water 
Limestones. By Samvet Hiszerrt, M. D., F.R.S. Ed., &c. 
&e. 
(Read December 2. 1833, February 17, April 21, and December 1, 1834.) 
INTRODUCTION. 
I propose in this memoir to methodically connect several 
desultory notices, which I had occasion to read during the last 
session of the Royal Society’s meetings, relative to the Lime- 
stones of fresh-water origin in the neighbourhood of Edinburgh, 
belonging to the carboniferous group of rocks, and to the organic 
remains which they contain. 
Hitherto, the limestones belonging to this older class of de- 
posits have been considered as exclusively of marine origin. I 
had long since, however, been prepared to expect that a lime- 
stone of a fluviatile or fresh-water origin would, some time or 
other, be proved to exist. For, in judging from analogy, it would 
be unreasonable to presume, that, when fresh-water limestones 
appear in the rocks of every later epoch, they should meet with 
an exclusion in the carboniferous group. In entertaining, there- 
fore, less confined. views, I was not at all surprised to find them 
confirmed in a limestone near Edinburgh, which lately came under 
my examination,—I allude to that of Burdiehouse. It enclosed 
none of the marine shells, corallines, or encrinites to be found in 
the other limestones of the vicinity, but contained in the place 
of them, and in the greatest possible abundance, the various 
plants observable in our coal-fields. I also procured from it 
VOL. XIII. PART I. Y 
