462 On the Post-Tertiary Beds | Oct., 
large series of well-preserved fossils, and when their relationships 
are fairly determined the key to many larger questions will be 
discovered. 
In order to commence one portion of the many investigations 
required, the writer, in company with a well-known Scotch 
naturalist (Mr. David Robertson), visited many of the Post-tertiary 
beds on the West of Norway, and in the present paper will endeavour 
to record a few results of the observations made. 
I. The first great series of shell-beds indicates the extremest 
degree of cold (as far as this can be indicated by any fauna) attained 
during the glacial epoch. 
These oldest Arctic shell-beds furnish a clear and definite starting 
point for our inquiries, and their analogies in Scotland and Norway, 
both in position and general character, are curious and instructive. 
The position of the shell-beds indicates the existence of glacial 
conditions previous to their deposition, together with the gradual 
submergence of the ice-clad land. In the west of Scotland the 
shell-bed rests upon a hard and compact clay, contaiming striated 
stones and travelled boulders, but devoid of fossils. The boulders 
and stones are in the larger proportion from neighbouring hills, a 
certain number however being always traceable to more distant 
heights. The force by which this clay was accumulated acted 
under local conditions, but extended from afar. The ‘striz upon 
the underlymg rock, and even upon enclosed fragments of shale, 
are so delicate that they indicate considerable slowness and gentle- 
ness of motion in the formative power, while the compactness 
of the mass indicates long-continued pressure, and not the drifting 
action of a storm. In one remarkable instance in Ayrshire a face 
of encrinal limestone has been exposed exquisitely polished. It 
rests beneath a mass of the clay now described and sections of 
encrinite are displayed in every position as perfectly as in any 
marble mantel-piece from Derbyshire. It may be noticed that in 
hollows the polishing process has been only half complete, but even 
when half complete it is almost more delicately worked than would 
be possible by the hand of man. 
The shell-beds of the west of Scotland rest in hollows washed 
out from this boulder clay, so that a long period of ice action pre- 
ceded the existence of the Arctic Fauna. There is evidence of the 
same fact in Norway. Resting upon the grooved and polished rocks 
at various points throughout the country, and reaching elevated 
positions on the mountain slopes, is a boulder clay which is precisely 
similar (local circumstances being taken imto account) to that so 
well known to Scotch geologists. This is older than the shell-clay. 
It contains no record of a fauna, and was probably produced by the 
action of land ice. A comparison between the two countries thus 
gives a well-marked period for further study, vz. the history of 
