8 
The Irish Naturalist 
January, 
Stated to belong probably to late Archaean times, and to have 
reached their present position as a result of earth-movements 
in early Devonian times. In some of the fluidal aplites the 
bands are made up of garnets, which Professor Cole considers 
indicative of the absorption of originally solidified material. 
We have a very distinct recollection of seeing a well developed 
crumpled structure, accompanied by step shearing, or faulting, 
in the banded gneisses in the vicinity of Lough Derg, Co. 
Donegal. One would like to know if this " pressure structure" 
is exceptional in the district ? 
Thk Ox Mountains. 
In his report on the Ox Mountains {Proc. R.I.A., vol. xxiv., 
sect. B., pt. 4, 1903) Mr. A. McHenry brings forward evidence 
that in this region pressure is the dominant factor in the pro- 
duction of "secondary" structures. He regards the rocks of 
this interesting region as being mainly metamorphosed Lower 
Silurian sediments, a small area (Croagh Patrick) being Upper 
Silurian. The highest beds are quartzites, and in descending 
order come the " Boulder-bed" limestone, black shales (Llan- 
deilo) and pebbly grits. Many of the large quartz pebbles in 
the latter are intensely sheared, and proof of this shearing is 
brought clearly before the reader in the form of numerous 
sketches made in the field. Basic and acid intrusions are 
sheared by the same movement, but much later granite 
intrusions are also present in the series. Referring to the 
Boulder-bed," it is interesting to note that Mr. McHenry 
thinks it probable that it represents a Palaeozoic glacial 
boulder-clay marking a break between the Lower and Upper 
Silurian formations in this part of Ireland. 
CARBONIFKROUS LAMEI.I.IBR anchiat a . 
At the end of 1904 the final portion of Dr. Wh^elton Hind's 
monograph on the above was published by the Palaeontographi- 
cal Society. Opportunity is taken to add in an appendix a 
description of additional species of interest, and amongst these 
we note a detailed description of a new genus Nothamusium^ 
the precise .systematic position of which is not as yet deter- 
mined. One species of two referred to this genus, and called 
