downwards. The slight touch is not noticed by the Bee, who continues
her work quite undisturbed; but the mark is not very deep and moreover
it is in a rather bad place for any prolonged experiment, for the Bee
is constantly brushing her belly to detach the pollen and is sure to
rub it off sooner or later. I therefore make another one, dropping the
sticky chalk right in the middle of the thorax, between the wings.

It is hardly possible to wear gloves at this work: the fingers need
all their deftness to take up the restless Bee delicately and to
overpower her without rough pressure. It is easily seen that, though
the job may yield no other profit, you are at least sure of being
stung. The sting can be avoided with a little dexterity, but not
always. You have to put up with it. In any case, the Mason-bee's sting
is far less painful than that of the Hive-bee. The white spot is
dropped on the thorax; the Mason flies off; and the mark dries on the
journey.

I start with two Mason-bees of the Walls working at their nests on the
pebbles in the alluvia of the Aygues, not far from Serignan. I carry
them home with me to Orange, where I release them after marking them.
According to the ordnance-survey map, the distance is about two and a
half miles as the crow flies. The captives are set at liberty in the
evening, at a time when the Bees begin to leave off work for the day.
It is therefore probable that my two Bees will spend their night in
the neighbourhood.

Next morning, I go to the nests. The weather is still too cool and the
works are suspended. When the dew has gone, the Masons begin work. I
see one, but without a white spot, bringing pollen to one of the nests
which had been occupied by the travellers whom I am expecting. She is