194 JOURNAL OF THE PLYMOUTH INSTITUTION. 
South Devon and Cornwall. The Clays on Torre Abbey Sands 
prove nothing, inasmuch as they prove a great deal too much. 
Moreover, the Clays in our creeks and inlets — which, by the way, 
instead of being " white," are at most drab, and not unfrequently 
blue — are far too modern for the service proposed for them. In- 
stead of being brought down by the overflow-waters of a Miocene 
Lake, they were unquestionably deposited in Post-Pliocene, indeed 
in Post-Glacial, times, and were the soil in which grew the Forests 
now submerged on our tidal strands. 
The plants which grew on the slopes surrounding the Bovey 
Lake — Cinnamons, Evergreen Figs, Laurels, Palms, and Ferns 
having gigantic rhizomes — have their existing congeners in a sub- 
tropical climate, such, it cannot be doubted, as prevailed in Devon- 
shire in Miocene times, and are thus calculated to suggest caution 
when the present climate of any district is regarded as normal. 
When, moreover, Miocene plants are found in Disco Island, on 
the west coast of Greenland, lying between 69° 20' and 70° 30' 
N. lat. ; when we learn that among them were two species found 
also at Bovey (Sequoia couttsice, and Quercus lyelli) ; when, to 
quote Professor Heer, we find that the "splendid evergreen" 
(Magnolia inglefieldi) " ripened its fruits so far north as on the 
parallel of 70°" (Phil Trans, clix., 457, 1869); when also the 
number, variety, and luxuriance of the Greenland Miocene plants 
are found to have been such that, had land continued so far, some 
of them would in all probability have flourished at the Pole 
itself, the problem of changes of climate is brought prominently 
into view, but only to be dismissed apparently with the feeling 
that the time for its solution has not yet arrived. 
It seems to be admitted on all hands that the Miocene plants 
of Europe have their nearest and most numerous existing analogues 
in North America, and hence arises the question, How was the 
migration from one area to the other effected? Was there, as 
some have believed, an Atlantis *? — a continent, or an archipelago of 
large islands, occupying the area of the North Atlantic. There is 
perhaps nothing unphilosophical in this hypothesis ; for since, as 
geologists state, " the Alps have acquired 4000, and even in some 
places more than 10,000 feet of their present altitude since the 
commencement of the Eocene period" (Lyell's Principles, 11th 
