--a fact
which makes many of his papers very difficult to understand--named the
worker after her work and called our builders in dried clay Mason-bees,
which describes them exactly.

We have two of them in our district: the Chalicodoma of the Walls
(Chalicodoma muraria), whose history Reaumur gives us in a masterly
fashion; and the Sicilian Chalicodoma (C. sicula) (For reasons that will
become apparent after the reader has learnt their habits, the author
also speaks of the Mason-bee of the Walls and the Sicilian Mason-bee
as the Mason-bee of the Pebbles and the Mason-bee of the Sheds
respectively. Cf. Chapter 4 footnote.--Translator's Note.), who is not
peculiar to the land of Etna, as her name might suggest, but is also
found in Greece, in Algeria and in the south of France, particularly in
the department of Vaucluse, where she is one of the commonest Bees to
be seen in the month of May. In the first species the two sexes are so
unlike in colouring that a novice, surprised at observing them come out
of the same nest, would at first take them for strangers to each other.
The female is of a splendid velvety black, with dark-violet wings. In
the male, the black velvet is replaced by a rather bright brick-red
fleece. The second species, which is much smaller, does not show this
contrast of colour: the two sexes wear the same costume, a general
mixture of brown, red and grey, while the tips of the wings, washed with
violet on a bronzed ground, recall, but only faintly, the rich purple of
the first species. Both begin their labours at the same period, in the
early part of May.

As Reaumur tells us, the Chalicodoma of the Walls in the northern
provinces selects a wall directly facing the sun and one not covered
with plaster, which might come off and imperil the future of the cells.
She confides her buildings only to solid foundations, such as bare
stones. I find her equally prudent in the south; but, for some reason
which I do not know, she here generally prefers some other base to the
stone of a wall. A rounded pebble, often hardly larger than one's fist,
one of those cobbles with which the waters of the glacial period covered
the terraces of the Rhone Valley, forms the most popular support.
The extreme abundance of these sites might easily influence the Bee's
choice: all our less elevated uplands, all our arid, thyme-clad grounds
are nothing but water-worn stones cemented with red earth. In the
valleys, the Chalicodoma ha