— ee 
161 
Pleistocene Depostts of Derbyshire and 
tts tnumedtate Vicinity, 
By Tuomas HEeatTu. 
GIERHAPS those experts who are acquainted with 
the meaning of the term Pleistocene, or Post- 
Pliocene, and the Geological period to which it 
especially refers, will be indulgent enough to bear with me while 
I very briefly explain it to those who have not made geology one 
of their special studies, so that they may be better able to follow 
me in my crude and imperfect remarks upon those Derbyshire 
remains which belong to this period. The difficulty of making 
such a technical abstract account of the “dry bones” of these 
deposits interesting will be obvious. 
As far as I am aware this is the period in which the first 
evidences of man appear; for most of this fauna is ‘‘ well known 
to have been contemporaneous with what is known as Palzolithic 
Man in Europe,” a subject which I shall venture to intrude upon 
the indulgence of the Society on a subsequent occasion. 
It is evident that the climatic conditions of that period differed 
considerably from the present. It covered a long period, in 
which is included our Glacial and Interglacial deposits. As 
Geikie says, ‘‘It was a period characterised by several 
extraordinary changes of climate, and certain considerable 
modifications in the outline of sea and land.” This is most 
obvious, from the fact that among the Pleistocene Mammalia 
- are well-marked Northern and Southern species; and so with 
the plants, and land and fresh water shells. Plant remains are 
not often found because of the nature of the alluvial sands, 
