five 848540] 
XXI.—_CAMBRO-SILURIAN AND SILURIAN ROCKS OF 
THE SOUTHERN AND THE WESTERN PARTS OF 
IRELAND. sy. G. H. KINAHAN, wm.p.a, &e. wir 
PLATE 8. 
[Read December 16, 1878. | 
In this paper it is proposed to give very briefly a general view 
of the Cambro-Silurian and Silurian formations, and their rela- 
tions to each other, as exhibited in the southward and westward 
parts of Ireland. 
Cambro-Silurians.—In the “Manual of the Geology of Ireland,” 
the Cambro-Silurians are separated into two divisions. This 
arrangement, perhaps, might be improved, by adding a third 
division, so as to classify the rocks as 
3. Upper Series. 
2. Ballymoney Series. 
1. Dark Shale Series. 
In the Slevenaman district, as also in the Galtees, there are 
purplish and greenish rocks somewhat like Cambrians in appear- 
ance, which Jukesregarded as possibly belonging to that formation. 
Until this autumn, I had not seen these rocks for a long time, 
some of them not for twenty-five years. I was aware that they 
had an aspect somewhat like Cambrians, and was inclined to sus- 
pect that they might be of that age. But last year Mr. James 
Budd, one of the Council of the Waterford Literary and Scientific 
Society, showed that the rocks at the Victoria Slate Quarries, in 
the vicinity of those just mentioned, in the Slievenaman district, 
contained Cambro-Silurian fossils ; and besides this, when I was 
comparing, last autumn, the Cambro-Silurians of Wexford with 
those of Munster, it seemed to me that those purplish and 
greenish rocks of Slievenaman, the Galtees, and Slieve-na-muck 
are higher in stratigraphical order even than the rocks of the 
Ballymoney series. 
The following appears to be a correct outline sketch of the 
rocks which form the subject of this paper. The Cambro- 
Silurians of southward and westward Ireland, lie in four about 
