way. The moment the punishment has been
administered, she returns to her post.

Next comes the turn of a Leaf-cutter (Megachile albocincta, PEREZ),
which, unskilled in the art of burrowing, utilizes, after the manner of
her kin, the old galleries dug by others. Those of the Zebra Halictus
suit her very well, when the terrible Gnat has left them vacant for
lack of heirs. Seeking for a home wherein to stack her robinia-leaf
honey-pots, she often makes a flying inspection of my colonies of
Halicti. A burrow seems to take her fancy; but, before she sets foot on
earth, her buzzing is noticed by the sentry, who suddenly darts out
and makes a few gestures on the threshold of her door. That is all. The
Leaf-cutter has understood. She moves on.

Sometimes, the Megachile has time to alight and insert her head into
the mouth of the pit. In a moment, the portress is there, comes a
little higher and bars the way. Follows a not very serious contest.
The stranger quickly recognizes the rights of the first occupant and,
without insisting, goes to seek an abode elsewhere.

An accomplished marauder (Caelioxys caudata, SPIN.), a parasite of the
Megachile, receives a sound drubbing under my eyes. She thought, the
feather-brain, that she was entering the Leaf-Cutter's establishment!
She soon finds out her mistake; she meets the door-keeping Halictus, who
administers a sharp correction. She makes off at full speed. And so with
the others which, through inadvertence or ambition, seek to enter the
burrow.

The same intolerance exists among the different grandmothers. About the
middle of July, when the animation of the colony is at its height, two
sets of Halicti are easily distinguishable: the young mothers and the
old. The former, much more numerous, brisk of movement and smartly
arrayed, come and go unceasingly from the burrows to the fields and from
the fields to the burrows. The latter, faded and dispirited, wander idly
from hole to hole. They look as though they had lost their way and were
incapable of finding their homes. Who are these vagabonds? I see in them
afflicted ones bereft of a family through the act of the odious Gnat.
Many burrows have been altogether exterminated. At the awakening of
summer, the mother found herself alone. She left her empty house and
went off in search of a dwelling where there were cradles to defend, a
guard to mount. But those fortunate nests already have their overseer,
the foundress, who, jealous of