Anniversary Address to the Royal Geological Society. 205 
conformably on the Glengariff Grits, and this is unquestionably a 
considerable difficulty. But the difficulty is somewhat lessened 
by taking the Grits on the S. side as being higher in the series 
than those on the N. side of Dingle Bay; he only offers this for 
as much as it is worth. There is another difficulty, though not a 
serious one—viz., that the Glengariff Grits of the Dingle Promon- 
tory are derived from Silurian rocks, They can, however, very 
well be Silurian for all that. 
Although, then, Griffith, in bringing out the later editions of 
his map, availed himself of the determinations of the Geological 
Survey when they recommended themselves to him, yet in the 
matter of the rocks now in question he maintained his opinion in 
opposition thereto. And it would appear now that the arrange- 
ment advocated by him will be introduced into future editions of 
the Survey maps. I understand that there is a contribution to 
the controversy to be presented to another Society almost imme- 
diately. As we have not this before us we shall not now go into 
the question. 
In the papers just mentioned Griffith speaks again of the 
Fintona, Curlew Mountain, and Croagh Moyle rocks, characterized 
by brown and reddish brown grits and conglomerates. There is, 
he says, a sufficient similarity to justify comparison between these 
and the Dingle and Glengariff strata. These were, from the first, 
coloured by him on his map as Old Red Sandstone (except that 
for a short time the Curlew Mountain rocks were marked as 
Yellow Sandstone). However, as we have seen, by the year 1843, 
he saw reason for doubting this arrangement, and he now repeats 
the arguments for connecting those rocks with the Upper Silu- 
rian; but whilst unacquainted with the real relations of the De- 
vonian he allows them to remain provisionally in this latter for- 
mation in deference to others, but distinguishes them in a note 
on his map. The Geological Survey have since taken these rocks 
in hand; but I do not know whether they have yet come to their 
final decision upon them. 
To the last we find certain districts, the largest of which is in 
Donegal and Londonderry, marked on the map as “ Primary.” 
Doubtless this was done at first in accordance with the views of 
the time ; and probably the title was afterwards continued for 
convenience, it not being intended to mean thereby more than 
