TRANSACTIONS OF THE SECTIONS. 49 
The fossils found in Egool consist of— 
Cephalopoda—Orthoceras imbricatum, Bellerophon dilatatus. 
Brachiopoda—Orthis rustica, O. semicircularis, O. radians, O. lata, Atrypa aspera 
Leptena depressa. 
Zoophyta—Stromatopora concentrica, Favosites alveolaris, F. fibrosa, F. spongites, 
F. polymorpha, Catenipora escharoides, Porites pyriformis, P. patelliformis, Acervu- 
_ laria Baltica, Limaria fruticosa, Turbinolopsis bina. 
" The whole number of described species found amounts to twenty-seven, of which 
nineteen occur in England—three in the Caradoc sandstone, and not above it, and 
sixteen in the Wenlock rocks, and the shale above them. 
It is to be observed, that the whole of the corals are found in an impure lime- 
_ stone, and none above or below it. 
Thus it appears that the reddish-brown sandstone district of the Curlew moun- 
tains comprehends a series of strata alternating with red sandstone and conglome- 
_ rate which contains sixteen varieties of fossils common to the Upper Silurian system 
of Murchison, and three to the Lower. 
It appears also that the small schistose districts at the base of the great sandstone 
at Pomeroy and Lisbellaw already mentioned, also contain numerous fossils belong- 
ing to the Silurian system, and many of which are common to the district of the Cur- 
lew mountains. These facts merit much consideration. If we class the sandstone and 
conglomerate with the Old Red system, the fossils which occur in beds interstratified 
with those rocks must be considered to belong to that system. If this be not ad- 
missible, then the sandstone and conglomerate of the Curlew mountains and the 
Pomeroy district must belong to the Silurian system. 
He would not enter into any further detail relative to the reddish-brown sand- 
stone of the North of Ireland, further than to point out another district of reddish- 
brown sandstone and conglomerate, situated to the north of Castlebar, and extending 
_ from Newport to Lough Conn in the county of Mayo, which is similar to the fore- . 
_ going, and which also lies unconformably beneath the carboniferous limestone at 
_ Castlebar; but as yet no fossiliferous beds have been discovered in it. 
_ ._ Myr. Griffith next directed the attention of the Section to a small district situated 
_ close to the town of Kildare, in the county of Kildare, in which he had lately dis- 
covered Silurian fossils. 
_ . This district is about three miles long and one broad, and extends from the Red 
Hills to Dunmurry Hill. The strata consist of alternations of gray limestone and 
_ gray clay-slate, both very fossiliferous. Among the fossils collected, thirty-two were 
_ known species ; eighteen of which have been described in the ‘Silurian System,’ all of 
which occur in the Caradoc sandstone, but five of them are common to the Wenlock 
and upper rocks. 
__ M+. Griffith next described another Silurian district, situated at the western extre- 
_ mity of the Peninsula of Dingle, in the county of Kerry. The strata consist of gray 
_ slates associated with red and gray quartzites, and occasionally conglomerates. The 
_ fossiliferous beds are numerous along the shore at Ferriter’s Cove, and also at Doon- 
_ quin, from whence they extend eastward into the country in the line of the strike. 
__ He also briefly noticed the occurrence of Silurian fossils in the gray slates of the 
% coast of Waterford,’ particularly at Knockmahon Copper-mines, Ballydowan Bay, and 
_ Tramore; and mentioned that this district had not yet been sufficiently examined, 
oe 
Le a 


ne 
B a that probably it extended beyond the limits marked out for it on his Geological 
_ Map. 
___ He observed, that in colouring the Geological Map, particularly in the south of 
__ Ireland, he experienced great difficulty in drawing a line of separation between the 
_ Silurian and old red sandstone groups ; the series evidently graduated into each other, 
and where fossils were wanting, lithological character formed his sole guide. He 
experienced considerable difficulty in determining to which group the chloritic and 
_ gray quartzites of the Gap of Dunloe near Killarney, of Macgillacudy’s Rocks, 
Mangerton, and the whole range of mountains extending thence to the eastward 
should be attached ; but finding similar green and gray quartzites associated with 
‘ the beds in which Silurian fossils occur in the Dingle Peninsula, and also in the 
Pgounty of Waterford, he thought it prudent provisionally to attach them to the Silu- 
; eo but he hoped still to find fossils which would determine the difficulty. 
. E 



