424 FIRST FORMS OF VEGETATION. 
circumstances, be easily neutralized or prevented 
by a little intelligent forethought, care, and in- 
dustry ; and providing incentives as they do to 
the exercise of these qualities, they compensate 
morally in some measure for the physical evils 
Fic. 52. 
(x) Spores or conidia of Botrytis infestans germinating. (2) The same 
sown artificially, and penetrating the tissues after eighteen hours. (3) 
Spore with contents differentiated. (4) Zoospore. (5) Zoospores germinating. 
(6) Zoospore sown artificially on the stem, and after twenty-four hours pene- 
trating the tissues and entering the intercellular spaces. 
they occasion. Certain conditions, as I have said, 
are necessary for their development, and it is to 
obviating and removing these that the builder and 
the farmer must look for exemption from the 
