f entomological nest-building,
especially where the cotton is of a brilliant white, as is frequently
the case in the manufacturers of the Girdled Anthidium. No bird's-nest,
however deserving of our admiration, can vie in fineness of flock, in
gracefulness of form, in delicacy of felting with this wonderful bag,
which our fingers, even with the aid of tools, could hardly imitate, for
all their dexterity. I abandon the attempt to understand how, with its
little bales of cotton brought up one by one, the insect, no otherwise
gifted than the kneaders of mud and the makers of leafy baskets, manages
to felt what it has collected into a homogeneous whole and then to work
the product into a thimble-shaped wallet. Its tools as a master-fuller
are its legs and its mandibles, which are just like those possessed by
the mortar-kneaders and Leaf-cutters; and yet, despite this similarity
of outfit, what a vast difference in the results obtained!

To see the Cotton-bees' talents in action seems an undertaking fraught
with innumerable difficulties: things happen at a depth inaccessible to
the eye; and to persuade the insect to work in the open does not lie
in our power. One resource remained and I did not fail to turn to
it, though hitherto I have been wholly unsuccessful. Three species,
Anthidium diadema, A. manicatum and A. florentinum--the first-named in
particular--show themselves quite ready to take up their abode in my
reed-apparatus. All that I had to do was to replace the reeds by glass
tubes, which would allow me to watch the work without disturbing the
insect. This stratagem had answered perfectly with the Three-horned
Osmia and Latreille's Osmia, whose little housekeeping-secrets I had
learnt thanks to the transparent dwelling-house. Why should it not
answer for its Cotton-bees and, in the same way, with the Leaf-cutters?
I almost counted on success. Events betrayed my confidence. For
four years I supplied my hives with glass tubes and not once did the
Cotton-weavers or the Leaf-cutters condescend to take up their quarters
in the crystal palaces. They always preferred the hovel provided by the
reed. Shall I persuade them one day? I do not abandon all hope.

Meanwhile, let me describe the little that I saw. More or less stocked
with cells, the reed is at last closed, right at the orifice, with
a thick plug of cotton, usually coarser than the wadding of the
honey-satchels. It is the equivalent of the Three-horned Osmia's
barri