The
experiment was repeated on the following year; and twenty protected
heads now yielded only a single aborted seed, whilst twenty heads on the
plants outside the net (which I saw visited by bees) yielded 2290 seeds,
as calculated by weighing all the seed, and counting the number in a
weight of two grains.
Trifolium pratense.--One hundred flower-heads on plants protected by a
net did not produce a single seed, whilst 100 heads on plants growing
outside, which were visited by bees, yielded 68 grains weight of seeds;
and as eighty seeds weighed two grains, the 100 heads must have yielded
2720 seeds. I have often watched this plant, and have never seen
hive-bees sucking the flowers, except from the outside through holes
bitten by humble-bees, or deep down between the flowers, as if in search
of some secretion from the calyx, almost in the same manner as described
by Mr. Farrer, in the case of Coronilla ('Nature' 1874 July 2 page 169).
I must, however, except one occasion, when an adjoining field of
sainfoin (Hedysarum onobrychis) had just been cut down, and when the
bees seemed driven to desperation. On this occasion most of the flowers
of the clover were somewhat withered, and contained an extraordinary
quantity of nectar, which the bees were able to suck. An experienced
apiarian, Mr. Miner, says that in the United States hive-bees never suck
the red clover; and Mr.
Pages:
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514