THE PHYSIOLOGY OF SOWING SEEDS. 613 
from insects eating the leaves, just alluded to. 
Besides, if by the spritting of potatoes, the whole 
of the diastase situated just below the bud, as it 
is just below the embryo in seeds, be expended, 
then there is no provision left for the conversion 
of fecula into saccharine matter for the formation 
of the first tissues of germination, and germina- 
tion must, therefore, fail. The corn weevil first 
destroys this substance in the grains, which it 
attacks in order that it may have the residue for 
its future consumption, when the season of ger- 
mination arrives. Frost liberates it in potatoes, 
and as its immediate action is the conversion of 
many hundred times its own volume of fecula 
into sugar; frosted potatoes are sweet in conse- 
quence. Indeed, in no case can germination 
ensue, without saccharine matter. The sap of 
trees is therefore highly charged with it in 
spring, before the expansion of the buds, as a 
provision to enable the buds to germinate. 
Keeping, then, these statements in mind, and 
considering that the cuttings of potatoes after 
all, are either planted upon, or under farm yard 
manure, in a highly azotised state, and frequently 
warm with fermentation, we need not be sur- 
prised that the germination of some of the 
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