140 Scientific Proceedings, Royal Dublin Society. 
they are, indeed, lithologically somewhat similar to the Comme- 
ragh Old Red Sandstone conglomerate ; but in the beds at the base 
of the Toor makeady conglomerate oe are Silurian fossils. 
Silurian fossils occur also a the very similar rocks of the Mweel- 
rea Mountains, north of Killary Harbour. These rocks are 
covered unconformably by the Carboniferous strata. 
Section IV.—North of Mweelrea, at Clew Bay, are the Louis- 
burgh and Clare Island beds representing in part the Dingle 
Beds. In these no typical Silurian fossils have been found; but 
lithologically they are similar, in part to the Mweelrea pebbly 
grits, and in part to the “Salrock Slates ;” the latter being the 
highest group in the Galway Silurians. 
Section V.—EKast and north-east of the head of Clew Bay are 
the Croaghmoyle conglomerates representing in part the Dingle 
Beds. No typical fossils have been found in them ; but lithologi- 
cally they are similar to the Toormakeady rocks and also to those 
in the Curlew Mountains, Cos. Sligo and Roscommon, next to be 
mentioned ; while they are capped unconformably by the Carboni- 
ferous rocks. 
Section VI.—The rocks near Ballaghaderreen and those of the 
Curlew Mountains are lithologically more or less similar to those 
already mentioned as representing the “Dingle Beds.” They 
extend downwards conformably into Silurians which contain 
fossils similar to those in the Silurians which, in the Co. Kerry, 
underlie the “ Dingle Beds ;” while above, as is the case with the 
“Dingle Beds,” they are cut off and are capped unconformably by 
the Carboniferous rocks. 
Section VII.—The rocks of the Fintona district, Cos. Ferma- 
nagh and Tyrone, are lithologically similar to those of the Curlew 
Mountains, and they likewise are capped unconformably by the 
Carboniferous rocks. They doubtless represent the Dingle Beds. 
Of these Portlock states that, in one place, they seem to lie confor- 
mably on the Cambro-Silurians. Griffith, however, mentioned to 
me in conversation that from information he had received, he 
suspected that in this district, as at Toormakeady, there would 
eventually be found at or near the base of the Fintona rocks a 
bed containing Silurian fossils. This supposition rests solely 
upon information supplied to him, which I have not had an 
opportunity of verifying. 
