144 THE GRAPE. 
ing them useless ; the leaves also will fall off after a short 
time, and the whole pliant become seriously injured 
These white patches are the fructification of the parasite; 
when viewed under the microscope, there is exhibited a 
multitudinous congregation of little mushroom-looking sub- 
atances, and if suddenly jerked, the tiny sporules may be 
seen detached, and floating in the atmosphere, so minute 
and subtle, and in such countless numbers, that it is not 
favorable influences) many are absorbed by the stomata or 
breathing pores on the under surface of the leaves, and 
conveyed into the interior, simply by the descending 
movement of the elaborated sap, oe is afterwards con- 
verted into woody-fibre, and in turn becomes the 
organized medium by which the poner sap, in the fol- 
lowing spring, flows with greater velocity to the unfolding 
leaves. ‘The secreted sporules may then be re-conducted 
wards, and conveyed onwards to the foilage, and there 
remain dormant, until the favorable circumstances occur 
for their germination, when they spring into renewed life, 
and speedily produce another crop of seeds for a future 
generation. This kind of mildew seldom does any mis- 
chief after the growth approaches towards ripeness, or the 
_ fruit is in the last swell, and as it generally begins to 
appear about the early part of July, during damp and 
close — those plants which have been more or less 
| by artificial heat are almost free from its attacks, 
be 
wie 
of FE exch fifteen or twenty square yards, and 
_ withhold water for the time being, k ’ 
elose, if cloudy, mod seing memes to vise some- 
