224 MIDLAND UNION OF NATURAL HISTORY SOCIETIES. OCT., 1892. 
distant views in the earlier part of the day, and all the 
arrangements were satisfactory. 
The coal measures over which the route lay at first lie 
buried by some considerable depth of glacial drift. Some 
evidence of coal-mining was, however, noticeable on the way 
to the Bwlch Quarry, and the fact of a thin seam of coal 
having been met with in the millstone grit when making the 
Llanforda tunnel for the Liverpool water works was pointed 
out. The eastern end of this same tunnel and the reservoir 
and filter-beds belonging to the Liverpool Lake Vyrnwy water 
supply, were seen from the road. The first halt was made at 
the Bwlch Quarry, about two miles from Oswestry. In this 
quarry, which presented a typical exposure of millstone grit, 
there was a zone of the usual hard, grey rock, several 
feet thick, in which plant remains, rootlets, etc., might 
be distinguished, proving it to be a shallow water or shore 
deposit. Upon this was lying a soft, sandy deposit, which 
was almost entirely made up of fossil shells of many different 
species, clearly indicating a deep sea origin for these strata. 
We have thus to picture a vast change, and periods of great 
submergence and upheaval following close on one another. 
In the sandy, fossiliferous strata, one of the party was 
fortunate enough to find the tail of a Trilobite, probably 
Phillipsia, a species which has once or twice before been found 
about this horizon in the millstone grit. This discovery was 
of interest as being the last appearance of the Trilobite in 
Geological time. 
At the Gloppa Sand Pit the party was made up to its full 
strength of forty or more by fresh arrivals, among whom were 
the president and others from Ellesmere, and Mrs. Barnes and 
her party from The Quinta. 
These sands, which lie at the north end of the Oswestry 
racecourse, are famous on account of the discovery here by 
A. 0. Nicholson, Esq., and others, of numerous shells in the 
sands and gravels, characteristic of the Glacial age, although 
the spot is now close upon 1,300 feet above the sea level. This 
fact demonstrates clearly to some minds the occurrence 
during the Glacial Epoch of a great subsidence of the land, 
whilst to others it has no such import; and these latter would 
have us believe that this and similar deposits are simply due 
to the glaciers having pushed up before them during their 
march overland the sand and gravel from some low-lying sea 
beach, and thus depositing it, shells and all, on the top of the 
hills. 
At 10 30 a move was made in the direction of the 
Carboniferous Limestone, and, at a mile distant, Offa’s Dyke 
was clearly seen crossing the line of the road N. and S., and 
