Bramble-Bees and Others

by Jean-Henri Fabre

These old observations on the habits of the Cylindrical Halictus may now be followed by a general summary which will incorporate the recent data supplied by the Zebra Halictus and the Early Halictus.

The females of the Cylindrical Halictus whom I unearth from November onwards are evidently fecundated, as is proved by the assiduity of the males during the preceding two months and most positively confirmed by the couples discovered in the course of my excavations. These females spend the winter in their cells, as do many of the early-hatching melliferous insects, such as Anthophorae and Mason-bees, who build their nests in the spring, the larvae reaching the perfect state in the summer and yet remaining shut up in their cells until the following May. But there is this great difference in the case of the Cylindrical Halictus, that in the autumn the females leave their cells for a time to receive the males under ground. The couples pair and the males perish. Left alone, the females return to their cells, where they spend the inclement season.

The Zebra Halicti, studied first at Orange and then, under better conditions, at Serignan, in my own enclosure, have not these subterranean customs: they celebrate their weddings amid the joys of the light, the sun and the flowers. I see the first males appear in the middle of September, on the centauries. Generally there are several of them courting the same bride. Now one, then another, they swoop upon her suddenly, clasp her, leave her, seize hold of her again. Fierce brawls decide who shall possess her. One is accepted and the others decamp. With a swift and angular flight, they go from flower to flower, without alighting. They hover on the wing, looking about them, more intent on pairing than on eating.

The Early Halictus did not supply me with any definite information, partly through my own fault, partly through the difficulty of excavation in a stony soil, which calls for the pick-axe rather than the spade. I suspect her of having the nuptial customs of the Cylindrical Halictus.

There is another difference, which causes certain variations of detail in these customs. In the autumn, the females of the Cylindrical Halictus leave their burrows seldom or not at all. Those who do go out invariably come back after a brief halt upon the flowers. All pass the winter in the natal cells. On the other hand, those of the Zebra Halictus move their quarters, meet the males outside and do not return to the burrows, which my autumn excavations always find deserted. They hibernate in the first hiding-places that offer.

In the spring, the females, fecundated since the autumn, come out: the Cylindrical Halicti from their cells, the Zebra Halicti from their various shelters, the Early Halicti apparently from their chambers, like the first. They work at their nests in the absence of any male, as do also the Social Wasps, whose whole brood has perished excepting a few mothers also fecundated in the autumn. In both cases, the assistance of the males is equally real, only it has preceded the laying by about six months.

So far, there is nothing new in the life of the Halicti; but here is where the unexpected appears: in July, another generation is produced; and this time without males. The absence of masculine assistance is no longer a mere semblance here, due to an earlier fecundation: it is a reality established beyond a doubt by the continuity of my observations and by my excavations during the summer season, before the emergence of the new Bees. At this period, a little before July, if my spade unearth the cells of any one of my three Halicti, the result is always females, nothing but females, with exceedingly rare exceptions.

True, it may be said that the second progeny is due to the mothers who knew the males in autumn and who would be able to nidify twice a year. The suggestion is not admissible. The Zebra Halictus confirms what I say. She shows us the old mothers no longer leaving the home but mounting guard at the entrance to the burrows. No harvesting- or pottery-work is possible with these absorbing doorkeeping-functions. Therefore there is no new family, even admitting that the mothers' ovaries are not depleted.

I do not know if a similar argument is valid in the case of the Cylindrical Halictus. Has she any general survivors? As my attention had not yet been directed on this point in the old days, when I had the insect at my door, I have no records to go upon. For all that, I am inclined to think that the portress of the Zebra Halictus is unknown here. The reason of this absence would be the number of workers at the start.

In May, the Zebra Halictus, living by herself in her winter retreat, founds her house alone. When her daughters succeed her, in July, she is the only grandmother in the establishment and the post of portress falls to her. With the Cylindrical Halictus, the conditions are different. Here the May workers are many in the same burrow, where they dwell in common during the winter. Supposing that they survive when the business of the household is finished, to whom will the office of overseer fall? Their number is so great and they are all so full of zeal that disorder would be inevitable. But we can leave this small matter unsettled pending further information.