602 
Cultivated Plants of the Future. 
and is making some exceedingly short cuts across this field of re- 
search, giving us artificial dyes, odours, flavours, and medicinal sub- 
stances, of such excellence that it sometimes seems as if before long 
the old-fashioned chemical processes in the plant itself would play 
only a subordinate part. But although there is no telling where the 
triumphs of chemical synthesis will end, it is not probable that it 
will ever interfere essentially with certain classes of economic plants. 
It is impossible to conceive of a synthetic fibre or a synthetic fruit. 
Chemistry gives us fruit-ethers and fruit-acids, and after a while 
may pi’ovide us with a true artificial sugar and amorphous starch ; 
but artificial fruits worth the eating or artificial fibres worth the 
spinning are not coming in our day. 
Despite the extraordinary achievements of synthetic chemistry, 
the world must be content to accept, for a long time to come, the 
results of the intelligent labour of the cultivator of the soil and the 
explorer of the forest. Improvement of the good plants we now 
utilise, and the discovery of new ones, must remain the care of large 
numbers of diligent students and assiduous workmen. So that, in 
fact, our question resolves itself into this : Can these practical inves- 
tigators hope to make any substantial advance 1 
It seems clear that, except in modern times, useful plants have 
been selected almost wholly by chance, and it may well be said that 
a selection by accident is no selection at all. Nowadays, the new 
selections are based on analogy. One of the most striking illustra- 
tions of the modern method is afforded by the utilisation of bamboo 
fibre for electric lamps. 
Some of the classes of useful plants must be passed by without 
present discussion ; others alluded to slightly, while still other 
groups fairly representative of selection and improvement will be 
more fully described. In this latter class would naturally come, of 
course, the food plants known as 
I. Tub Cbf.eals. 
The species of grasses which yield these seed-like fruits, or as we 
might call them for our purpose seeds, are numerous ; twenty of 
them are cultivated largely in the Old World, but only six of them 
are likely to be very familiarly known — namely, wheat, rice, barley, 
oats, rye, and maize. The last of these is of American origin, despite 
doubts which have been cast upon it. It was not known in the Old 
World until after the discovery of the New. It has probably been 
very long in cultivation. The others all belong to the Old World. 
Wheat and barley have been cultivated from the earliest times ; 
according to De Candolle, the chief authority in these matters, about 
four thousand years. Later came rye and oats, both of which have 
been known in cultivation for at least two thousand years. Even 
the shorter of these periods gives time enough for wide variation, 
and as is to be expected there are numerous varieties of them all. 
If the Chinese records are to be trusted, rice has been cultivated 
for a period much longer than that assigned by our history and 
