MISCELLANEOUS PLANTS 289 
widely scattered. Professor Asa Gray lists seven species of 
Allium as growing wild in northeastern North America, only 
one of which is naturalized from Europe. May not this also be 
a case of multiple domestication, if the writer may coin a term 
to indicate what he believes to have been a common thing in 
the early days of civilization ? 
The beet (Beta vulgaris). \Whether as a garden delicacy or a 
food for stock, this plant is no mean addition to our gardens 
and fields, but as a sugar plant it ranks as of prime importance. 
It is the one plant that has made sugar production possible in 
the temperate zones. Beginning with but 3 or 4 per cent of 
sugar, by careful breeding it has been raised in sugar content 
till whole fields average 14, and single specimens have been 
found above 25 per cent. This achievement is mainly the re- 
sult of German enterprise, and shows what science can do 
when applied to the ordinary affairs of life.’ 
The beet yet grows wild in the Canary Islands and all along 
the Mediterranean, and as far east as Persia and Babylon. It 
was cultivated by the Greeks and Romans, though its varieties 
have been greatly increased of late ; indeed, it seems to be one 
of these fortunate species that is growing in favor, just as salsify 
is as certainly dying out. 
Manioc, or mandioca (Manihot utilissima). This plant, of great 
significance in tropical agriculture, would not be mentioned here 
except for the fact that it is almost undoubtedly another of the 
American, and therefore comparatively late, contributions to the 
agriculture of the world, and except for the further fact that it 
is the source of our tapioca of commerce. The arguments for 
its western nativity lie in the fact of its comparatively ancient 
cultivation in tropical America, and the further fact that the 
1 This was not the result of accident, but of deliberate determination. The 
Germans felt the disadvantage of depending solely on the tropics for their 
sugar supply, and government chemists were set at work to discover, if possible, 
a sugar-bearing plant that could be raised in their latitude. The result is that 
beet sugar can compete in price with the cane, and the quality is not only 
equal but identical. 
