GEOLOGICAL SOCIETY OF DUBLIN. 
9 
districts. And here I may observe that we arrive at the point which will 
he found to he the commencement of our difficulties; and I propose to 
limit the observations I shall have to make in the remainder of the 
present communication to a statement respecting the relations of the 
rocks of the Dingle Peninsula, and to a comparison of those rocks with 
the strata which comprise the district south of the town of Killorglin 
and Dingle Pay, extending as far south as the valley of Kenmare; and I 
shall conclude by an endeavour to show that an analog yexists between 
the brownish-red grits of the north of Ireland, to which I have already 
alluded, and certain strata of the southern districts to which I shall pre¬ 
sently advert; hoping that by such a comparison I may be able to con¬ 
tribute towards a removal of the difficulties with which the subject is at 
present surrounded. 
The district of the peninsula of Dingle may be said to contain three 
principal classes of rocks, the first of which is the undoubted Old Red Sand¬ 
stone, similar to that of Waterford, Tipperary, and Kilkenny, to which I 
have just referred. These strata consist of alternating beds of red conglo¬ 
merate, red and gray sandstones, with reddish and greenish shales, 
and they rest at various inclinations on the edges of vertical and much 
disturbed strata, the classification of which latter presents the difficulty 
with which we have to contend. I may mention a few localities where 
the clearest unconformable junctions between these two series of rocks 
occur. We have them clearly exhibited north of Castlemaine Harbour; 
also at Peenoskee, in the precipice over a lake on the east side; and at 
Carrignaspaniagh, which is the continuation of the Cahirconree range; and 
again, to the south of Prandon Pay; so that, in a section extending from 
thence in a south-eastern direction, we have four repetitions of uncon¬ 
formable junction across the peninsula. In the face of the mountain of 
Caherconree another remarkable unconformable junction may be ob¬ 
served, the underlying vertical strata presenting zig-zag flexures, pro¬ 
bably the evidence remaining of some prior movement. I have prepared 
a section* at right angles to the former, running nearly north and south 
across the promontory, from Tralee Pay to Castlemaine Harbour, in 
which some of the unconformable junctions are exhibited, and they will 
be found to be indisputable. At Eduard, about 700 feet above the level 
of the sea, east of Dingle Harbour, we have an outlier of nearly hori¬ 
zontal beds of Old Red Sandstone resting unconformably upon vertical 
beds of brownish-red conglomerate, and occasionally red slate; and at 
Sybil Head, on the western shore of the peninsula, we meet a similar 
junction. Continuing across Smerwick Harbour, from Dunurlin Head 
to Pallydavid Head, and thence to Prandon Head, we find the same 
unconformities presented as at Sybil Head, as well as south of Toom- 
paun Mountain, near Prandon Head, where at Pierasmore, two small 
outliers rest unconformably, and nearly horizontally, on the greenish- 
gray and brownish-red conglomerate and slates of Prandon Mountain. 
* See Plate V. 
VOL. V.-PEOC. soa 
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