On the other hand he
fertilised about 30 flowers with pollen from the long-styled form, and these,
with the exception of two, yielded capsules, containing good seeds.
It is a singular fact, in contrast with what occurred in the case of L.
grandiflorum, that the pollen-grains of both forms of L. perenne, when placed on
their own-form stigmas, emitted their tubes, though this action did not lead to
the production of seeds. After an interval of eighteen hours, the tubes
penetrated the stigmatic tissue, but to what depth I did not ascertain. In this
case the impotence of the pollen-grains on their own stigmas must have been due
either to the tubes not reaching the ovules, or to their not acting properly
after reaching them.
The plants both of L. perenne and grandiflorum, grew, as already stated, with
their branches interlocked, and with scores of flowers of the two forms close
together; they were covered by a rather coarse net, through which the wind, when
high, passed; and such minute insects as Thrips could not, of course, be
excluded; yet we have seen that the utmost possible amount of accidental
fertilisation on seventeen long-styled plants in the one case, and on eleven
long-styled plants in the other, resulted in the production, in each case, of
three poor capsules; so that when the proper insects are excluded, the wind does
hardly anything in the way of carrying pollen from plant to plant.
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