88 PLANT LIFE ON THE FARM. 
continues, ‘‘ who trailed ropes over their flowering wheat 
to insure complete fertilization, were doing that which 
the very appearance of the anthers told them in whispers, 
not yet heard, had already been accomplished.” The 
pollen of these plants which the winds disperse, is not 
that which fertilizes, but that which is not required for 
fertilization. The success of the process depends, as 
before said, upon the circumstance whether or not the 
pollen and the feathery stigma are respectively ripe at 
the same time. If so, then fertilization results ; if not, 
there is still a chance of cross-fertilization, but if that 
fail, the flower remains barren. 
Hybridization is a procedure with which the gardener 
is much more familiar than the farmer. It is only a 
further development of cross-fertilization. Cross-fertili- 
zation, as has been said, takes place between flowers of 
the same individual plant, or between flowers of two dif- 
ferent individuals of the same species ; but hybridization 
is effected by crossing the flowers of two separate species, 
as in the case of the Alsike clover, which is said to be a 
hybrid between the white or Dutch clover and the red 
clover. 
Chemical Ghanges,—The chemical changes which oc- 
cur during the formation of the flower, and especially 
during the ripening of the seed, have already been alluded 
to. The contrast between the composition of the leaves 
and that of the pollen and of the seeds is very striking, 
and analysis brings out the fact of the accumulation of 
nitrogenous and phosphatic and mineral matters in the 
pollen and in the seed. In haymaking it is better, if 
possible, to mow before the leaves are exhausted of their 
contents by the seeds, or at any rate, before the latter are 
shed. If cutting be delayed, a great part of the nutritive 
matter is withdrawn from the leaves and stem to be 
