FLORA, 599 
There are supplied details relative to indications of the 
times at which different trees mentioned in this table and 
allies of these had made their appearance at different 
places, and it is added that amongst Arctic species may 
be mentioned the following as having been the stock from 
which have sprung the European and American plants of 
the present day, the names of which are associated with 
them in the following list :— 
Artic Miocene Forms, DERIVED sp OF THE PRESENT 
IME, 
Potamogeton Nordenskjéld, Hr... Potamogeton natans L.—Europe. 
Quercus groénlandica Hr............ Quercus prinus L.—America. 
Ulmus Braunii Hr...........0.:000008 Ulmus campestris L.—Europe. 
Menyanthes arctica Hr.............. Menyanthes trifoliata L.—Europe. 
Viburnum Whymperi Hr........... Viburnum lantana L.—Europe. 
Hedera Mac-Cluri Hr. ............... Hedera helix L, Var. hibernis,— 
Europe. 
Acer otopteryX GDp....cesescereeeee Acer dasycarpum Michx. —America. 
Juglans acuminata Al. Br. Juglans regia L.—Europe. 
Sorbus grandifolia Hr........ Sorbus aria L.—Europe. 
Prunus staratschini Hr.............. Prunus spinosa L.—Kurope. 
Crataegus oxyacanthoides Gp...... Crataegus oxyacantha L,—Europe. 
After some other remarks in elucidation of what has 
been advanced, Count Saporta goes on to say:—‘ We 
must go about 30 degrees of latitude towards the south 
to find, growing wild and associated in an analogous con- 
dition, the vegetable forms which flourished then in the 
Polar zone. The lands of that zone, at the time of which 
a portion of their secret has now been revealed to us, 
formed then a vast expanse, perhaps the only continent of 
the time. These lands were at the same time affected by 
the interior fire, exposed to incessant eruptions, and sub- 
jected to the overflow of Basalt. It is known that such 
a state of things is no obstacle in the way to the advance- 
ment of vegetation, and that it even favours in some cases 
its development in spite of the partial devastations which 
it brings in its train, Auvergne and the Cantal in France 
have been equally with this region, in a later age, 
the theatre of the same phenomena; and the abundance 
of imprints left on the ashes and volcanic mud attest that 
