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.