tting loose my insects! When half-way, to
make my experiment more decisive still, I repeat the rotation, in as
complicated a fashion as before. I repeat it for the third time at the
spot chosen for the release.

I am at the end of a flint-strewn plain, with here and there a scanty
curtain of almond-trees and holm-oaks. Walking at a good pace, I
have taken thirty minutes to cover the ground in a straight line. The
distance therefore is, roughly, two miles. It is a fine day, under a
clear sky, with a very light breeze blowing from the north. I sit down
on the ground, facing the south, so that the insects may be free to take
either the direction of their nest or the opposite one. I let them loose
at a quarter past two. When the bags are opened, the Bees, for the most
part, circle several times around me and then dart off impetuously in
the direction of Serignan, as far as I can judge. It is not easy to
watch them, because they fly off suddenly, after going two or three
times round my body, a suspicious-looking object which they wish,
apparently, to reconnoitre before starting. A quarter of an hour later,
my eldest daughter, Antonia, who is on the look-out beside the nests,
sees the first traveller arrive. On my return, in the course of the
evening, two others come back. Total: three home on the same day, out of
ten scattered abroad.

I resume the experiment next morning. I mark ten Mason-bees with red,
which will enable me to distinguish them from those who returned on
the day before and from those who may still return with the white spot
uneffaced. The same precautions, the same rotations, the same localities
as on the first occasion; only, I make no rotation on the way, confining
myself to swinging my box round on leaving and on arriving. The insects
are released at a quarter past eleven. I preferred the forenoon, as this
was the busiest time at the works. One Bee was seen by Antonia to be
back at the nest by twenty minutes past eleven. Supposing her to be the
first let loose, it took her just five minutes to cover the distance.
But there is nothing to tell me that it is not another, in which case
she needed less. It is the fastest speed that I have succeeded in
noting. I myself am back at twelve and, within a short time, catch three
others. I see no more during the rest of the evening. Total: four home,
out of ten.

The 4th of May is a very bright, calm, warm day, weather highly
propitious for my experiments. I take