p her quarters, tiny
creature that she is, in the spiral staircase of Bulimulus radiatus. It
is a very elegant, but very small lodging, to say nothing of the fact
that a considerable portion is taken up with the green-putty plug. There
is just room for two.

The Andrenoid Osmia (O. andrenoides, LATR.), who looks so curious, with
her naked red abdomen, appears to build her nest in the shell of the
Common Snail, where I discover her refuged.

The Variegated Osmia (O. versicolor, LATR.) settles in the Garden
Snail's shell, almost right at the bottom of the spiral.

The Blue Osmia (O. cyanea, KIRB.) seems to me to accept many different
quarters. I have extracted her from old nests of the Mason-bee of the
Pebbles, from the galleries dug in a roadside bank by the Colletes (A
short-tongued Burrowing-bee known also as the Melitta.--Translator's
Note.) and lastly from the cavities made by some digger or other in the
decayed trunk of a willow-tree.

Morawitz' Osmia (O. Morawitzi, PEREZ) is not uncommon in the old nests
of the Mason-bee of the Pebbles, but I suspect her of favouring other
lodgings besides.

The Three-pronged Osmia (O. tridentata, DUF. and PER.) creates a home of
her own, digging herself a channel with her mandibles in dry bramble and
sometimes in danewort. It mixes a few scrapings of perforated pith with
the green paste. Its habits are shared by the Ragged Osmia (O. detrita,
PEREZ) and by the Tiny Osmia (O. parvula, DUF.)

The Chalicodoma works in broad daylight, on a tile, on a pebble, on a
branch in the hedge; none of her trade-practises is kept a secret from
the observer's curiosity. The Osmia loves mystery. She wants a dark
retreat, hidden from the eye. I would like, nevertheless, to watch
her in the privacy of her home and to witness her work with the same
facility as if she were nest-building in the open air. Perhaps there are
some interesting characteristics to be picked up in the depths of her
retreats. It remains to be seen whether my wish can be realized.

When studying the insect's mental capacity, especially its very
retentive memory for places, I was led to ask myself whether it would
not be possible to make a suitably-chosen Bee build in any place that I
wished, even in my study. And I wanted, for an experiment of this sort,
not an individual but a numerous colony. My preference leant towards the
Three-horned Osmia, who is very plentiful in my neighbourhood, where,
together with Latreille's O