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Easky, there is an elongated sinous eskers nearly parallel to tlie 
line of tlie valley ; it is composed altogether of pebbles of quartz 
and mica slate, mixed with sand and clay, all derived from the 
adjoining mountains, thus forming a moraine, which may be ac- 
counted for on the hypothesis of Agassiz. Following the valley 
of Lough Easky to the sea-shore, a distance of ten miles, the 
entire surface of the limestone country is thickly strewed with 
large boulders of granite ; some of these close to the shore are of 
enormous dimensions ; one of them being about one hundred 
tons in weight. They occur also along the whole hne of coast 
westward, from Easky to Erris, in Mayo, and with them a few 
rolled blocks of mica slate, occasionally, but no limestone, though 
the entire district, which is comparatively low and flat, is com- 
posed of strata belonging to the carboniferous system. These 
granite boulders are precisely similar in composition to the 
granite of Lough Easky, Lough Talt and Foxford. Taking all 
these facts into consideration, it is evident that in these localities 
the currents must have been from the south, and not, as iu 
other districts of Ireland, from the north-west to the south-east. 
On the Lower Portion of the Carboniferous Limestone Series of 
Ireland, by R. Griffith, Esq. 
This communication was accompanied by numerous large 
coloured sections, which illustrated the author^s minute descrip- 
tions of particular localities. The carboniferous rocks, as sub- 
divided by Mr. Griffith, are in descending order as follows : — 1 . 
The upper limestone forms the base of the millstone grit series; 
it averages 600 feet in thickness, and is very fossilliferous in its 
upper part. 2. The Calp series consists of a succession of dark 
gray slates alternating with dark impure limestone ; beds of yel- 
lowish sandstone occupy the middle of the series, which is 
usually 1000, and occasionally 1800 feet thick. The shales of 
this division contains numerous fossils, especially Posidoniss, of 
which there are six species. 3. The lower limestone occupies a 
very considerable portion of Ireland, and contains a great abun- 
