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and the reader is referred for further information to the works of Sir J. Lubbock and of Darwin. The latter, in his work on “Cross and Self Fertilisation of Plants,” gives the strongest evidence as to the beneficial influence of bees upon clover-crops. At page 169, when speaking of the natural order of leguminous plants, to which the clovers belong, he says, “The cross-seedlings have an enormous advantage over the self-fertilised ones when grown together in close competition”; and in Chapter X, page 361, he gives the following details of some experiments, which show the importance of the part played by bees in the process of cross-fertilisation:-
Trifolium repens (White Clover). —Several plants were protected from insects, and the seeds from ten flower-heads on these plants and from ten heads on other plants growing outside the net (which I saw visited by bees) were counted, and the seeds from the latter plants were very nearly ten times as numerous as those from the protected plants. The experiment was repeated in the following year, and twenty protected heads now yielded only a single abortive seed, whilst twenty heads on the plants outside the net (which I saw visited by bees) yielded 2,290 seeds, 28 calculated by weighing all the seeds and counting the number in a weight of 2 grains.
Trifolium pratense (Purple Clover).—One hundred flower-heads on plants protected by a net did not produce a single seed, whilst one hundred on plants growing outside (which were visited by bees) yielded 68 grains' weight of seed; and, as eighty seeds weighed 2 grains, the hundred heads must have yielded 2,720 seeds.
Here we have satisfactory proof that the effect of cross-fertilisation brought about by bees upon the clovers and other plants growing in meadows and pasture-lands is the certain production of a large number of vigorous seeds, as compared with the chance only of a few and weak seeds if self-fertilisation were to be depended upon. In the case of meadow-cultivation it enables the farmer to raise seed for his own use or for sale, instead of having to purchase it, while at the same time the nutritious quality of the hay is, as we shall see further on, improved during the process of ripening the seed. In the case of pasture-lands, such of those vigorous seeds as are allowed to come to maturity and to fall in the field will send up plants of stronger growth to take the place of others that may have died out, or to fill up hitherto-unoccupied spaces, thus tending to cause a constant renewal and strengthening of the pasture. The agriculturist himself should be the best judge of the value of such effects.
The beneficial effect of the bees' visits to fruit-trees has been well illustrated by Mr. Cheshire in the pages of the British Bee Journal, and by Professor Cook in his articles upon “Honey Bees and Horticulture” in the American Apiculturist. (See also “Bulletin No. 18, Bee-culture,” New Zealand Department of Agriculture.) In fact, even those who complain of bees cannot deny the services they render; what they contest is the assertion that bees do no harm.
