662 C. CALLAWAY ON THE PRECAMBRIAN 
hornstone, like one of the Lilleshall rocks, and a chocolate felstone 
with a few scattered prisms of felspar, very similar to some of the 
Wrockwardine types. This conglomerate shades off gradually, both 
above and below, into the ordinary Longmynd sandstones. ‘There 
is little doubt that this band has been derived from the series de- 
scribed. 
I have already mentioned that on the N.W. flank of the Ragleth 
and further to the 8.W., the Longmynd series is represented by a 
felspathic sandstone. This rock is chiefly made up of quartz and a 
red felspar, and it is highly probable that it has been produced by 
the degradation of the granitoid series. 
In my paper “On the Quartzites of Shropshire” (Q. J. G. 8. xxxiv. 
p. 760), I state that “towards its base the quartz-rock contains 
fragments derived from the older series, consisting of small rounded 
or unrounded pieces of felstone greatly decomposed, but in some 
cases showing distinctly the banded structure characteristic of some 
of the Wrekin felstones.” As the quartzite is of (at least) Lower 
Cambrian age, the felstone must be Precambrian. Professor Bonney 
has examined some of these specimens, and he quite confirms my 
previous opinion (Note D, p. 666). 
GENERAL SUMMARY. 
1. The axial chain of hills in South Shropshire must be removed 
from the category of intrusive greenstones, and regarded as built up 
of bedded rocks broken through by later basic eruptions. 
2. The chain is flanked by various formations from the Lower 
Cambrian to the Trias. Some of the flanking deposits, which are of 
(at least) Lower Cambrian age, are partially or wholly derived from 
the axial rocks. By the double test of stratigraphical position and 
included fragments the bedded part of the chain is thus shown to be 
of Precambrian age. 
3. The lithology of the chain is very varied. (1) Metamorphic 
rocks of Malvernian (the author) or Dimetian (Professor Bonney) 
type. (2) Volcanic (Mr. Allport, Professor Bonney, and the author). 
(3) Sedimentary, as conglomerate, grit, claystone, and shale. 
4. The separate masses composing the chain are wedges of the 
solidified crust thrust up through younger deposits between great 
parallel S.W. faults. The structure of the ridges is plagioclinal 
(the strikes being across the axis), and their direction is determined 
by the faults. 
Notes on the Microscoric Srrucrure of some SHROPSHIRE Rocks. 
By Prof. T. G. Bonnny, M.A., F.R.S., Sec. GS. 
Av Ercal Hill, to the north of the Rhyolites of the Wrekin, so 
admirably described by Mr. 8. Allport*, is a mass of reddish granitoid 
* Quart. Journ. Geol. Soc. vol. xxxiii. p. 449, &e. 
