on the
ceiling, is not bad to begin with; but to use it for making a work of
art is better still. The honey has disappeared. Now commences the final
weaving of the cocoon. The grub surrounds itself with a wall of silk,
first pure white, then tinted reddish-brown by means of an adhesive
varnish. Through its loose-meshed stuff, it seizes one by one the
droppings hanging from the scaffold and inlays them firmly in the
tissue. The same mode of work is employed by the Bembex-, Stizus-and
Tachytes-wasps and other inlayers, who strengthen the inadequate woof
of their cocoons with grains of sand; only, in their cotton-wool purses,
the Anthidium's grubs substitute for the mineral particles the only
solid materials at their disposal. For them, excrement takes the place
of pebbles.

And the work goes none the worse for it. On the contrary: when the
cocoon is finished, any one who had not witnessed the process of
manufacture would be greatly puzzled to state the nature of the
workmanship. The colouring and the elegant regularity of the outer
wrapper of the cocoon suggest some kind of basket-work made with tiny
bits of bamboo, or a marquetry of exotic granules. I too let myself be
caught by it in my early days and wondered in vain what the hermit of
the cotton wallet had used to inlay her nymphal dwelling so prettily
withal. To-day, when the secret is known to me, I admire the ingenuity
of the insect capable of obtaining the useful and the beautiful out of
the basest materials.

The cocoon has another surprise in store for us. The end containing the
head finishes with a short conical nipple, an apex, pierced by a narrow
shaft that establishes a communication between the inside and the
out. This architectural feature is common to all the Anthidia, to the
resin-workers who will occupy our attention presently, as well as to the
cotton-workers. It is found nowhere outside the Anthidium group.

What is the use of this point which the larva leaves bare instead of
inlaying it like the rest of the shell? What is the use of that hole,
left quite open or, at most, closed at the bottom with a feeble grating
of silk? The insect appears to attach great importance to it, from what
I see. In point of fact, I watch the careful work of the apex. The grub,
whose movements the hole enables me to follow, patiently perfects the
lower end of the conical channel, polishes it and gives it an exactly
circular shape; from time to time, it inserts into th