The eggs, after the fourth day, instead of changing in the manner of caterpillars, were found in the same state they were in the first day, except that some were covered with honey. A singular event happened the next day, about noon; all the bees left their own hive, and were seen attempting to get into a neighbouring one, on the stool of which the queen was found dead, being no doubt slain in the engagement. This event seems to have arisen from the great desire of perpetuating their species, and to which end the concurrence of the males seems so absolutely necessary; it made them desert their habitations, where no males were left, in order to fix a residence in a new one, in which there was a good stock of them. To be further satisfied, Mr. Debraw took the brood-comb, which had not been impregnated, and divided it into two parts; one he placed under a glass bell, No. 1, with honey-comb for the bees food, taking care to leave a queen, but no drones, among the bees confined in it; the other piece of the brood-comb he placed under another glass bell, No. 2, with a few drones, a queen, and a proportionable number of common bees. The result was, that in the glass, No. 1, there was no impregnation, the eggs remaining in the same state they were in when put into the glass; and on giving the bees their liberty on the seventh day, they all flew away as was found to be the case in the former experiment; whereas in the glass, No. 2, the very day after the bees had been put into it, the eggs were impregnated by the drones, and the bees did not leave their hive on receiving their liberty.
The editor of the Cyclopædia says, that the small drones are all dead before the end of May, when the larger species appear, and supersede their use; and that it is not without reason that a modern author suggests, that a small number of drones are reserved to supply the necessities of the ensuing year; but that they are very little, if any, larger than the common bee.
It does not enter into our plan to notice further in this place the wonders of this little society. A bee-hive is certainly one of the finest objects that can offer itself to the eyes of the beholder. It is not easy to be weary of contemplating those workshops, where thousands of labourers are constantly engaged in different employments.[83]
[83] The remarks made by the late Mr. Hunter on the experiments of Messrs. Schirach and Debraw, in my opinion, merit the attention of the reader; they are contained in his “Observations on Bees,” comprizing a variety of information respecting the history and œconomy of those curious insects. This ingenious and interesting account is inserted in the Philosophical Transactions for the year 1792, page 128-195. I cannot altogether subscribe to his opinion relative to the minuteness and prolixity of Swammerdam. Edit.
OF THE EGGS OF INSECTS.
The eggs are contained and arranged in the body of the insect, in vessels which vary in number and figure in different species; the same variety is found in the eggs themselves: some are round, others oval, some cylindrical, and others nearly square; the shells of some are hard and smooth, while others are soft and flexible. It is a general rule, that eggs do not increase in size after they are laid; among insects, we find however an exception to this; the eggs of the tenthredo of Linnæus increase after they are laid, but their shell is soft and membranaceous. The eggs of insects differ in their colours; some may be found of almost every shade, of yellow, green, brown, and even black. The eggs of the lion puceron,[84] hemerobius, Lin. are very singular objects, and cannot have escaped the eye of any person who is conversant among the insects which live on trees; though of the many who have seen them, few, if any, have found what they really were. It is common to see on the leaves and pedicles of the leaves of the plumb-tree, and several other trees, as also on their young branches, a number of long and slender filaments, running out to about an inch in length; ten or twelve of these are usually seen placed near one another, and a vast number of these clusters are found on the same tree; each of these filaments is terminated by a sort of swelling or tubercle of the shape of an egg. They have generally been supposed to be of vegetable origin, and that they were a sort of parasitical plant growing out of others. There is a time when these egg-like balls are found open at the ends; in this state they very much resemble flowers, and have been figured as such by some authors, though they are only the shells of the eggs out of which the young animals have escaped after being hatched. If these eggs be examined by a microscope, a worm may be discovered in them; or they may be put into a box, in which, in due time, they will produce an insect, which, when viewed with a microscope, will be found to be the true lion puceron.
[84] Reaumur Hist. de Insectes, vol. xi. p. 142.
Divine Providence instructs the insects, by a lower species of perception, to deposit their eggs not only in safety from their numerous enemies, but also in situations where a sufficient quantity of food is on the spot to support and nourish the larva immediately on breaking the shell. Some deposit their eggs in the oak leaf, producing there the red gall; others choose the leaf of the poplar, which swells into a red node or bladder; to a similar cause we must attribute the red knob which is often seen on the willow leaf, and the three pointed protuberances upon the termination of the juniper branches. The leaves of the veronica and cerastium are drawn into a globular head by the eggs of an insect lodged therein. The phalæna neustria glues its eggs with great symmetry and propriety round the smaller branches of trees. Fig. 1. [Plate X.] represents a magnified view of the nest of eggs taken off the tree after the caterpillar had eaten its way through them; the strong ground-work of gum, by which they are connected and bound together, is very visible in many places; they strengthen this connection further, by filling up all the intervening space between the eggs with a very tenacious substance. These eggs are crustaceous, and similar to those of the hen; Fig. 2 represents the natural size. Fig. 3 is a magnified vertical section of the eggs, shewing their oval shape; Fig. 4 the natural size. Fig. 5 is an horizontal section through the middle of the egg, and Fig. 6 the same not magnified. It is not easy to describe the beauty of these objects, when viewed in the lucernal microscope; the regularity with which they are placed, the delicacy of their texture, the beautiful and ever-varying colours which they present to the eye, give the spectator a high degree of rational delight.
In the Lapland Alps there is a fly covered with a downy hair, called the rhen-deer gad-fly, oestrus tarandi, Linn. it hovers all day over these animals, whose legs tremble under them; they prick up their ears, and flee to the mountains covered with ice and snow to escape from a little hovering fly, but generally in vain, for the insect but too soon finds an opportunity to lodge its egg in the back of the deer; the worm hatched from this egg perforates the skin, and remains under it during the whole winter: in the following year it becomes a fly. The oestrus bovis is an equal terror to oxen; the hippobosca equina, to horses; oestrus ovis,[85] to the sheep, &c.
[85] Oestrus ovis in naso sive sinu frontis animalium rumenantium. Linn.