1874.] Climate of the Glacial Period. 439 
Harmer, or by ice, as suggested by Mr. Croll, these broken 
and fragmentary shells—mixed through other transported 
material evidently ice-borne—are the débris of beds older 
than those in which they are now found. The Foraminiferze 
of the same deposits have been examined by Messrs. Cross- 
key and Robertson: they, like the shells, are much worn, 
and present a more arctic character, varied by the presence 
of one or two Tertiary forms.* Altogether it appears that 
the deposits have been formed by the mixing together of the 
shells of two or more periods; and we might just as readily 
infer an arctic climate from the artic shells and Forami- 
niferee as a more southern one from the few fragments of 
species characteristic of the coralline crag, and which 
were probably derived from beds of that age in the neigh- 
bourhood. 
In Ireland the shells found in the drift also indicate a 
colder climate than the present, and in Scandinavia the only 
evidence of the warm periods of Mr. Croll’s theory, advanced 
by Mr. Geikie, points in reality to the opposite conclusion ; 
that is to say, beds in Scania, described by M. Nathorst, 
containing Arctic plants—amongst others Salix Polaris, now 
confined to the Arétic Circle,—which indicate a climate more 
‘severe than that of Northern Norway. These and other 
beds so far north are valuable, as evidence that the ice did 
not destroy all remains of the vegetation that had flourished 
in the so-called “‘inter-glacial period,’ and if during that 
time more southern forms had ever advanced northwards 
we ought somewhere to find their remains. 
In North America there is, again, no evidence of a warmer 
climate having prevailed in inter-glacial times; the marine 
shells and the vegetable remains all point either to more 
Arctic conditions, or to a climate not warmer than the 
present. 
But, even if we could bring ourselves to believe that all 
the remains of the southern faunas and floras had been 
destroyed by the ice of the Glacial period, whilst the more 
Arctic forms had been preserved, we ought surely to find 
some evidence of the warm climates to the south of the limit 
to which the ice extended. In Sicily are preserved abun- 
dance of memorials of the cold climate of the Glacial period, 
when Alpine ice filled all the lakes of North Italy, covered 
the plains of Piedmont and Lombardy, and cooled the waters 
of the Mediterranean so that it was occupied by more 
* Introduction to Crag Mollusca. By S. V. Woop, Jun., and F. W. 
HarMer. P._22. 
