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dyke of amygdaloid greenstone which cuts through the graywacke 
and is lost in the sea; and the other is near Loch Connell, where a 
mass of greenstone extends in a westerly direction for nearly two 
miles. At both localities, the trap intersects the graywacke ; but at 
neither point could the author find it in contact with the coal or over- 
lying breccia. 
3. Coal Measures. A deposit consisting of beds of red and white 
sandstones, clays and micaceous shale, similar to those of the coal- 
field of Ayr, has been long known to exist in the district, and has 
led to several fruitless researches for coal. The deposit may be 
traced for about nine miles, forming a narrow band parallel to Loch 
Ryan. The beds are in general moderately inclined to the E. or 
S.E. In a quarry on the farm of Clachan, Mr. Moore found re- 
mains of Stigmaria ficoides, and in another, on the farm of Chal- 
lock, an abundance of Calamites. 
4. Red Breccia. This rock extends from the bay of Sloughna- 
garry to the farm of Dumlae, a distance of eight miles, forming a 
ridge from 200 to 300 feet high, between the coal measures and the 
shore of Loch Ryan. It consists entirely of irregular fragments of 
graywack cemented by a red clayey sand, but in some places it 
passes into lamine of red sandstone. The beds are nearly horizon- 
tal or dip slightly to the S.E., and rest on the coal measures. As Mr. 
Moore did not detect any organic remains in the breccia, nor find 
any rock overlying it, he does not offer an opinion respecting the 
period of its formation. 
A paper was afterwards read, “On the Siliceous Bodies of the 
Chalk, Greensand and Oolites ;’ by Mr. Bowerbank, F.G.S. 
The author commences by stating, that naturalists and geologists 
have long considered the form of tuberous masses of flint found in 
the upper chalk to be due to alcyonia or sponges, but that he is not 
aware of this opinion having been proved to be correct. It was 
Professor Ehrenberg’s observations on siliceous bodies which first 
induced him to obtain thin slices of flint with the intention of pro- 
curing specimens of Xanthidium. In the examination of these slices, 
he was struck with the frequent occurrence of patches of brown, re- 
ticulated tissue, spicula and foraminifera, and he was induced to 
infer, that the patches of tissue were the remains of the organized 
body, possibly a sponge, to which the flint owed its form. With this 
belief, he commenced his inquiries by examining thin slices of flints 
obtained from various localities, and he found in all of them, a per- 
fect accordance in the structure and proportion of reticulated tissue, 
in the number of spicula, and in the occurrence of Xanthidia and 
Foraminifera. The following are the general appearances which the 
slices of flint exhibit when mounted upon glass. 
With a power of about 120 linear, the slice presents the appear- 
ance of a stratum of a turbid solution of decomposed vegetable or 
animal matter containing foraminifera, spicula, Xanthidia, and fre- 
quently fragments of the brown tissue. In a specimen from North- 
fleet the mass of the spongeous portion exhibited numerous cylin- 
