A. R. Horwood— Upper Trias, Leicestershire. 3871 
of the Coal-measures presented an uneven surface for the deposition 
of different members of the Trias upon it, being also attenuated to 
the south-east from the north and west, as seen from numerous 
colliery sections. ‘This overlap is reflected in the discordance between 
the strike of the different members of the Trias. 
Another feature is the gradual passage of the Lower Keuper 
Sandstones into the Marls, as noted at Austrey and Warton, and of 
the lateral passage of the sandstones into marls at Heather. This 
feature is paralleled in the Upper Keuper Sandstone by the thinning 
of the marls to the west and the sandstones to the east at Leicester, 
near Hinckley Road, and at Ashleigh House. In such cases we have 
instances of the occurrence of lenticular bands. 
The river development of the Trias depends upon the fact that the 
main systems of drainage are developed along the line of strike 
(Caledonian in direction) of the Soar, excavated in the softer beds of 
the Red Marl. A similar feature is to be noticed in the Mease 
Valley where the valley forms the junction between the Lower 
Keuper Sandstones and Red Marls. No doubt the original systems 
of consequents and subsequents, with the resulting obsequents 
developed on a more ancient peneplain, is to a large extent modified 
as regards the Red Marl area in Leicestershire, so far as the present 
peneplain is concerned by the markedly radial arrangement of streams 
which are dependent upon the relation of the Red Marl to the old 
developed surfaces of Charnwood Forest. The developing of this 
area before the deposition of the Trias caused the system of drainage 
which largely contributed to the sediments forming the Trias and 
earlier rocks locally to some extent. The later development of the 
Red Marls since their deposition and formation of the present contours 
has been the work of numerous agents of denudation, subaerial in the 
main, before glacial time, which we have no means of determining. 
But elacial action itself has paved the way for much of the present 
system of drainage, causing radial arrangement of streams, together 
with the agencies that have regulated the present systems of con- 
sequents and subsequents upon which this radial system is superposed. 
In this way the river drainage west of the Soar ‘Valley differs from 
that to the east except whens. as around Billesdon, a similar radial 
arrangement may also be discerned in beds older than the Trias. 
6. PrerrograPHy anD LirHonoey. 
As this section affords material for a separate paper, and, owing to 
reasons into which I need not enter, a bare summary of this even 
could not be prepared, I have decided to omit this section from the 
present paper. Reference to ‘‘The British Trias, a Delta System” 
(Trans. N. Staffs Field Club, vol. xlvii, pp. 100-30) will afford a very 
brief summary of the character of the sediments examined in this 
area, together with a comparison between them and the deposits in 
other parts of the country. 
(To be concluded in our next Number.) 
