J. J. Swammerdam, son of an apothecary at Amsterdam, carried the investigation of the hive-bee much further than any naturalist before him, though he did not exhaust it. He proved definitely that the so-called "king of the bees" was really a queen and the only effective female in a hive. The chief part of his work was done in 1673, when the dykes were cut to save Amsterdam from the French invasion, so that the hives in Holland were ruined, and scarcely any queens could be procured. Swammerdam spent many months upon the investigation of bees, and took scrupulous pains in examining their structure and habits. Referring to his Biblia Natura, in which the hive-bee is described, Prof. Miall says:

The life-history, the anatomy of the male, female and neuter bees in every stage, and the whole economy of the hive, are carefully described . . . The engraved figures would do credit to the most skilful anatomists of any age. This, the first extensive and truly scientific memoir on the hive and its inhabitants, carries the exploration a long way at a single bound, and biology can hardly produce a second example of a research so comprehensive and disfigured by so few faults.

Réaumur extended the knowledge of the honeybee still further by studies of the living insect in observation hives; Schirach, in 1771, proved that worker-bees are imperfect females, and the history of the wedding-flight was first correctly described by Huber in 1814. Finally, Dzierzon, in the middle of the nineteenth century, showed that the eggs laid by unwedded queens give birth to drones; that the fertilisation of the queen takes place within a few days of her quitting her cell, and lasts for life; and that female. bees (queens and workers) proceed only from eggs fertilised by drones. Queens and workers are respectively produced from female bees by being fed on different

foods while in their larval state. The future queen is fed on 66 chyle food" by the nurses until it assumes the chrysalis change, from which it emerges a perfect female. The future worker is weaned upon the fourth day, and fed henceforth on honey and digested pollen, with the result that it remains an undeveloped female.

This wonderful history of the hive-bee represents the results of work done by naturalists of many countries and at different times. There have been hundreds of practical bee keepers from ancient to modern times, but they have contributed almost nothing to this knowledge of the structure and functions of the complicated social community of a hive; and for the actual fact we have to go to Butler, Bonnet, Swammerdam, Réaumur, Huber, Dzierzon, and other inquiring naturalists whose names are unfamiliar not only to general readers but also to a large part of the scientific world.

Three hundred years ago little was known of the transformation which insects undergo from the egg to the fly emerging from the larval skin. Harvey, the discoverer of the circulation of the blood, was so far mistaken as to teach that insects were generated by chance, and that the change from a pupa to the winged form was a transmutation like that of a base metal into gold, or the flying nymph of Ovid into a laurel tree. He regarded the pupa as an egg; and even now the pupae of ants are popularly called ants' “ eggs. Swammerdam persistently pointed out the errors of this belief, and by his studies disposed of it completely. He proved that all the parts of an insect are beneath the larval skin long before the insect emerges; that, in fact, the larva or pupa is not transmuted into a butterfly but is the butterfly itself in another form.

By his laborious studies in the latter half of the seventeenth century, Swammerdam worked out the complete transformation of insects, and recognised the chief types of development. For his facts he went direct to Nature, and he was rarely deceived by her. Upon most of the subjects studied by him, philosophers and other schoolmen had been content to pass on fantastic ideas without inquiry into their veracity. Aristotle, Vergil, Pliny and other early writers, all agreed that certain bees, which may sometimes be seen carrying small stones as they fly, do so to prevent being blown out of their course in windy weather. The conclusion was childish, but it was sufficient for writers who had not watched the habits of this insect-the mason-bee. When actual observation was made by Swammerdam, nearly two thousand years later, he found that the stones were used by the bee to strengthen its hive.

Aphids, or plant-lice, are familiar to every gardener, yet how few know anything of their life-history or of the patient work of investigators who revealed it. When, toward the end of the seventeenth century, the evercurious naturalist, Antony Van Leeuwenhoek, began to study the insects, he sought for their eggs, but without success. Later, he made the surprising discovery that aphids brought forth their young alive, and upon opening an aphis only a fortnight old he found no fewer than sixty young ones in it. Réaumur extended Leeuwenhoek's observations, and showed that both the winged and wingless aphids could produce living young. He tried to isolate aphids from birth to see if they would still continue to increase their kind, but was prevented by accidents from concluding his observations. When, therefore, Charles Bonnet (1720-1793) asked him to suggest a subject of investigation, the unfinished

experiment was proposed as one likely to lead to interesting results. Bonnet was only twenty years of age when he undertook this task.

He filled a flower-pot with earth, and plunged it into a phial of water, intended to supply the food-plant. A new-born aphis, whose birth had been observed, was placed on the plant, and all was covered up by a bell-jar, which was pressed into the earth, so as to exclude other insects. An aphis found upon the spindle-tree was selected for the first trial, which began on May 20, 1740. Bonnet kept an exact diary of his observations, which were made hourly or oftener during the day; a good lens was continually employed. The aphis changed its skin four times, and came to maturity on June 1, when the first young one was born. By June 21, the unfertilised female had produced 95 aphids, all born alive. Prof. L. C. Miall.

A similar result was obtained the next year, when two new-born aphids, isolated in the same way, produced respectively 90 and 49 young. Five successive generations of aphids were then bred without the participation of a male insect, and the result, which was contrary to all that was then known of reproduction in nature, was received with lively interest not unmixed with incredulity. The life-history of these insects differs indeed from all pre-conceived ideas. Bonnet's observations established it to be as follows: both winged and wingless aphids produce young alive while food is plentiful, but as the winter approaches this mode of reproduction ceases; small winged males then appear, and the females lay fertilised eggs from which young aphids emerge in the following spring. Aphids are thus born without the participation of the male insect during mild weather, and their race is carried on from one year to another by the eggs laid by fertile females near the end of the season.

The discovery of this intricate course of events is far more wonderful than the achievement of any Arsène

Lupin or Sherlock Holmes of fiction. There are winged and wingless females both producing live young without any eggs or the intervention of the male, winged insects which produce no young, and eggs from which young emerge; and the problem was to find the clue which connected these various threads into a skein of evidence. Leeuwenhoek, Réaumur and Bonnet were the chief detectives in this case, and their work, though unknown to the world at large, claims the admiration of all who will consider it.

The mantle of the French naturalist, Réaumur, fell upon J. H. Fabre, and in these two faithful observers France can claim possession of the greatest students of insect-life the world has ever seen. Fabre, born in poverty and earning for himself and family a salary of £64 a year as a schoolmaster, "less," as he says, "than a groom in a well-to-do household," produced works on the habits of insects which stand by themselves, whether we consider them as science or literature. So long ago as 1871, Darwin, in his Descent of Man, referred to Fabre as "that inimitable observer," and Maurice Maeterlinck has happily named him "The Insects' Homer." In his Souvenirs Entomologiques, Fabre recorded in ten volumes the results of fifty years of observation, study and experiment on living insects of the South of France.

In 1843, when eighteen years of age, Fabre, with his teacher's certificate, was appointed to take charge of a primary school at Carpentras, at a salary of £28 a year. He there met for the first time the black mason-bee which makes nests of clay on pebbles or a wall and fills them with honey. Réaumur dedicated one of his studies to this interesting insect, but Fabre did not then know of it. He spent a month's salary in the purchase