R. Colgate informs me that he has observed the
same fact in New Zealand after the introduction of the hive-bee into
that island. On the other hand, H. Muller ('Befruchtung' page 224) has
often seen hive-bees visiting this plant in Germany, for the sake both
of pollen and nectar, which latter they obtained by breaking apart the
petals. It is at least certain that humble-bees are the chief
fertilisers of the common red clover.
Trifolium incarnatum.--The flower-heads containing ripe seeds, on some
covered and uncovered plants, appeared equally fine, but this was a
false appearance; 60 heads on the latter yielded 349 grains weight of
seeds, whereas 60 on the covered-up plants yielded only 63 grains, and
many of the seeds in the latter lot were poor and aborted. Therefore the
flowers which were visited by bees produced between five and six times
as many seeds as those which were protected. The covered-up plants not
having been much exhausted by seed-bearing, bore a second considerable
crop of flower-stems, whilst the exposed plants did not do so.
Cytisus laburnum (Leguminosae).--Seven flower-racemes ready to expand
were enclosed in a large bag made of net, and they did not seem in the
least injured by this treatment. Only three of them produced any pods,
each a single one; and these three pods contained one, four, and five
seeds. So that only a single pod from the seven racemes included a fair
complement of seeds.
Pages:
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515