Kohl says, "like a huge giant in his seven-league boots."
Thousands of them are annually blown into the Black Sea, and here,
once in contact with water, in an instant lose the fantastic grace
belonging to their dry, unsubstantial texture.'

Any one who has seen the feather-like seeds of thistles and dandelions
floating about in the air, will have little difficulty in
comprehending the effect of winds on the distribution of vegetation.
Such seeds, as Mr Henfrey observes, might readily be carried across
Europe by a powerful autumn gale, blowing steadily in one direction.
In physiological language, they belong to the _sporadic_, not to the
_endemic_ class, of which a remarkable instance is afforded in the
flea-bane (_Erigeron canadensis_), a plant which, having found its way
to this side the Atlantic only since the discovery of America, is now
a common weed on the continent of Europe. Running streams and ocean
currents also transport seeds from one locality to another. The
gulf-stream, as is well known, carries occasionally branches of trees
to the north coast of Scotland and Norway; and 'Mr Brown found that
six hundred plants collected about the river Zaire, in Africa,
included thirteen species, natives also of Guyana and Brazil. These
species mostly occurred near the mouth of the Zaire, and were of such
kind as produced fruits capable of resisting external agencies for a
long time.' Then, again, the agency of birds, of quadrupeds, and of
man, in the distribution of seeds and plants, is too important to be
overlooked, as Sir Charles Lyell has ably shewn in his _Principles of
Geology_; and there is 'a certain number of plants which seem to
accompany man wherever he goes, and to flourish best in his vicinity.
Thus, the docks, the goosefoots, the nettle, the chickweed, mallows,
and many other common weeds, seem to be universal, though unwelcome
companions to man--dogging his footsteps, affording by their presence,
even in now deserted districts, an almost certain index of the former
residence of human beings on the spot.'

From an examination of the causes affecting distribution, Mr Henfrey
passes to a survey of the characteristics of the countries of Europe,
from north to south--from the peninsula of Scandinavia to those of
Spain, Italy, and Greece. The remarkable contrast is pointed out
between the climate and cultivation of the east and west sides of the
mountains of Sweden and Norway. Barley ripens as far north as the 7