GEOLOGICAL SOCIETY OE DUBLIN. 
79 
I cannot conclude this part of the subject without alluding to the 
remarkable paper by Dr. Falconer, read before the London Geological 
Society, on the different species of Mastodon, particularly those found in 
the British strata. He draws a marked distinction between the Mas¬ 
todon angustideus and Mastodon arvernensis, contrary to the views of 
Cuvier and Owen. The former he considers peculiar to the miocene 
strata, the latter to the pleiocene. He further concludes:— 
1. That the Mastodon remains, found both in the fiuvio-ma/rine or 
Norwich crag , and red crag , belong to the pleiocene form, Mastodon 
( tetralophodon ) arvernensis. 
2. That the mammalian Fauna of the fluvio-ma/rine crag bears all 
the character of the pleiocene age, and is identical with the sub-Appennine 
pleiocene Fauna of Italy. 
3. That the red and fluvio-marine crags, tested by their mammalian 
Fauna, must be considered as beds of the same geological age. 
It is very much to be desired that Dr. Carte, or some person equally 
well qualified, would undertake the publication of a monograph of the 
Irish fossil mammalian remains. 
I shall now touch upon some subjects more closely connected with 
Irish Geology; and, in the first place, I rejoice to find that Professor 
Haughton is not relaxing in his inquiries as to the mineral composition 
of the Irish rocks. 
He read to us a paper on the Siliceo-felspathic Bocks of the south of 
Ireland, which affords some remarkable results. These rocks are situ¬ 
ated in the mining district of Ovoca, and county of Wicklow; in the 
district of Bonmahon, county of Waterford; and also in the neighbour¬ 
hood of Killarney and Kenmare Bay, in the county of Kerry. They re¬ 
semble much in chemical composition, though not in appearance, the 
elvans of Cornwall, and the miners consider that they have an equally 
favourable effect on the mineral lodes. They are, however, frequently 
deposited in stratified bed, conformable to the slates and felspathic ash- 
beds in which they are situated. Professor Haughton has analyzed with 
his usual care several specimens of these rocks, and the conclusions he 
comes to are as follows :— 
Per cent. 
Bell Bock, Yale of Ovoca—Quartz,.45*54 
,, „ Orthoclase felspar, . . . . 54*16 
99*70 
Bocks of Bonmahon, Co. Waterford—Quartz, . . . . 40*81 
,, ,, Orthoclase felspar, 57*19 
,, ,, Carbonate of lime, 1 *81 
99*81 
