and the species of Andropogon, ^Egilops, &c. by separate sexes, exhibit tro- 
pical qualities. The Grasses are also less gregarious, and meadows seldomer 
occur, in the south than in the north of Europe. 
“ As to what relates to the distribution of individuals, the generality of 
species are social plants. 
“ A detailed representation of the distribution of the cultivated Gramina 
would certainly be very interesting. Here we must restrict ourselves to 
a short and general outline. We shall endeavour to specify those Gramina 
which are the prevailing ones in the large zones and continents, mentioning, 
in passing, those plants of other families which either supply the place of, 
or are associated with, the different kinds of grain, as the chief article of 
food. The distribution is determined, not merely by climate, but depends 
on the civilisation, industry, and traffic of the people, and often on historical 
events. 
“ Within the northern polar circle, agriculture is found only in a few 
places. In Siberia grain reaches at the utmost only to 60°, in the eastern 
parts scarcely above 55°, and in Kamtchatka there is no agriculture even in 
the most southern parts (51°). The polar limit of agriculture on the north- 
west coast of America appears to be somewhat higher ; for, in the more 
southern Russian possessions (57° to 52°), barley and rye come to maturity. 
On the east coast of America it is scarcely above 50° to 52°. Only in Europe, 
namely, in Lapland, does the polar limit reach an unusually high latitude 
(70°). Beyond this, dried fish, and here and there potatoes, supply the place 
of grain. 
“ The grains which extend farthest to the north in Europe are barley and 
oats. These, which in the milder climates are not used for bread, afford to 
the inhabitants of the northern parts of Norway and Sweden, of a part of Si- 
beria and Scotland, their chief vegetable nourishment. 
“ Rye is the next which becomes associated with these. This is the pre- 
vailing grain in a great part of the northern temperate zone, namely, in the 
south of Sweden and Norway, Denmark, and in all the lands bordering on the 
Baltic ; the north of Germany, and part of Siberia. In the latter another 
very nutritious grain, buck-wheat, is very frequently cultivated. In the 
zone where rye prevails, wheat is generally to be found ; barley being here 
chiefly cultivated for the manufacture of beer, and oats supplying food for the 
horses. 
“To these there follows a zone in Europe and western Asia, where rye 
disappears, and wheat almost exclusively furnishes bread. The middle, or the 
south of France, England, part of Scotland, a part of Germany, Hungary, the 
Crimea and Caucasus, as also the lands of middle Asia, where agriculture is 
followed, belong to this zone. Here the vine is also found ; wine supplants 
the use of beer ; and barley is consequently less raised. 
“ Next comes a district where wheat still abounds, but no longer exclu- 
sively furnishes bread, rice and maize becoming frequent. To this zone be- 
long Portugal, Spain, part of France on the Mediterranean, Italy, and 
Greece ; further, the countries of the East, Persia, northern India, Arabia, 
Egypt, Nubia, Barbary, and the Canary Islands ; in these latter countries, 
however, the culture of maize or rice towards the south, is always more con- 
siderable, and in some of them several kinds of Sorghum (Doura) and Poa 
Abyssinica come to be added. In both these regions of wheat, rye only oc- 
curs at a considerable elevation ; oats, however, more seldom, and at last 
entirely disappear ; barley afifording food for horses and mules. 
“ In the eastern parts of the temperate zone of the Old Continent, in China 
and Japan, our northern kinds of grain are very unfrequent, and rice is found 
to predominate. The cause of this difference between the east and the west 
