Experiences the same pleasurable thrill as did the skeppist of old at the sight of the first drone of the year, which betokens an early swarm.
But flies of the drone-fly kind cannot sting, and, so far as is known, are perfectly innocuous and edible.
It is believed that from the nature of the cell in which she is ovipositing, the queen derives a reflex impulse to lay the appropriate egg - fertilized in the queen or worker cell, unfertilized in the drone cell, as previously mentioned.
In the nests of Bombi are found various beetle larvae that live as inquilines or parasites, and also maggots of drone-flies (V olucella), which act as scavengers; the Volucella-fly is usually a" mimic ' vades.
(3) That birds may also be deceived by insects that mimic those they have found to be uneatable has been shown by the abovequoted experiment with the drone-fly and the honey-bees made by Professor Lloyd Morgan.
Weismann, however, doubts these conclusions, and having found a spermaster in every one of the eggs that he examined from workercells, and in only one out of 272 eggs taken from drone-cells, he supports Dzierzon's view, explaining the single exception mentioned above as a mistake of the queen, she having laid inadvertently this single fertilized egg in a drone instead of in a worker cell.
But if it be discovered, as is possible, that the drone-fly is also inedible, the mimicry must be ascribed to the Mullerian category, and the reason for it becomes less evident.
This forcibly suggests that the drone-fly mimics a honey-bee not only in appearance but also in the feel of its hairs or the nature of its buzz.
In the case of the common drone-fly, Eristalis tenax, the individual, from a sedentary maggot living in filth, without any relations of sex, and with only unimportant organs for the ingestion of its foul nutriment, changes to a creature of extreme alertness, with magnificent powers of flight, living on the products of the flowers it frequents, and endowed with highly complex sexual structures.