552 Notices of Memoirs—Prof. Hull—Rocks under Trias. 
colour renders the study of their relations to each other in the field 
a comparatively easy task. The gabbro, which overlies the grano- 
hyre, was the first-formed rock, and had already cooled and 
solidified before the granophyre was injected into it. The injection 
of granophyre has been of the most searching character, and the 
rock can be traced from the parent mass through dykes of all 
gradations in size down to the minutest films and specks which fill 
cracks and cavities: in and amongst the constituent minerals of the 
gabbro. The gabbro has thus become converted locally into the 
quartz gabbro of authors, and it is suggested that in other cases, as 
that of Carrock Fell, this rock has had a similar origin. The grano- 
phyre, on the other hand, contains fragments of the gabbro, ranging 
from great blocks down to mere crystal dust of its constituent 
minerals, labradorite and augite. It thus passes into hornblendic 
granophyre, the ‘‘syenite” of the Survey. There is no evidence here, 
as has been erroneously supposed, of the differentiation of an origin- 
ally homogeneous magma, and the minute granophyric dykes are 
neither contemporaneous nor segregation products. On the contrary, 
rocks of intermediate character have been produced from already 
differentiated and opposed types solely by admixture. 
VI.—Own tHE Discovery or A ConcEALED RIDGE OF PRE-CARBONTI- 
FEROUS Rocks UNDER THE T'RIAS oF NETHERSEAL, LEICESTER- 
SHIRE. By Professor Epwarp Hutt, LL.D., F.R.S., F.G.S. 
T is now generally recognised that the Leicestershire and 
Warwickshire Coal-measures were deposited along the borders 
of a land surface of older Paleozoic rocks, of which the visible 
representatives occur at Charnwood Forest and Atherstone. The 
attenuated condition of the Lower Carboniferous beds at Calke 
Abbey on the north of the Leicestershire Coalfield, and their entire 
absence below the Coal-measures of Warwickshire, show that these 
older rocks remained unsubmerged till the commencement of the 
Upper Carboniferous period, when they were gradually overspread, 
as the land became depressed, by successive deposits of the Coal | 
period. The general north-westerly trend of these old foundation 
rocks, both at Charnwood Forest and Atherstone, appears to indicate 
that this old land was composed of a succession of ridges and 
furrows running in N.W. and §.E. directions; but as the country 
is for the most part covered by Triassic strata the position of such 
ridges and hollows can only be determined by experiment. One of 
these ridges appears to have been in this manner determined at 
Netherseal Colliery in a boring put down for the purpose of deter- 
mining the extension of ‘the main coal.” Having been invited by 
Mr. G. J. Binns, F.G.S., the manager of the colliery, to give my 
opinion regarding the age of the beds passed through in the lower 
part of the boring, I visited the colliery and inspected the cores 
which were brought up and were arranged in their order of relative 
depth at the works. The following is an abstract of the strata 
passed through :— 
