for a bedchamber wherein to take the long sleep which is
the prelude to the metamorphosis. Bulging with fat, it is a rich and
defenseless morsel for whoever is able to reach it. Then, in spite
of apparently insurmountable obstacles, the mortar wall and the tent
without an opening, the flesh-eating larvae appeared in the secret
retreat and are now glutting themselves on the sleeper. Three different
species take part in the carnage, often in the same nest, in adjoining
cells. The diversity of shapes informs us of the presence of more than
one enemy; the final stage of the creatures will tell us the names and
qualities of the three invaders.

Forestalling the secrets of the future for the sake of greater
clearness, I will anticipate the actual facts and come at once to the
results produced. When it is by itself on the body of the mason bee's
larva, the murderous grub belongs either to Anthrax trifasciata, MEIGEN,
or to Leucospis gigas, FAB. But, if numerous little worms, often a score
and more, swarm around the victim, then it is a Chalcidid's family which
we have before us. Each of these ravagers shall have its biography. Let
us begin with the Anthrax.

And first the grub, as it is after consuming its victim, when it remains
the sole occupant of the mason bee's cocoon. It is a naked worm, smooth,
legless and blind, of a creamy dead white, each segment a perfect ring,
very much curved when at rest, but with the tendency to become
almost straight when disturbed. Through the diaphanous skin, the lens
distinguishes patches of fat, which are the cause of its characteristic
coloring. When younger, as a tiny grub a few millimeters long, it is
streaked with two different kinds of stains, some white, opaque and of a
creamy tint, others translucent and of the palest amber. The former
come from adipose masses in course of formation; the second from the
nourishing fluid or from the blood which laves those masses.

Including the head, I count thirteen segments. In the middle of the body
these segments are well marked, being separated by a slight groove; but
in the forepart they are difficult to count. The head is small and is
soft, like the rest of the body, with no sign of any mouth parts even
under the close scrutiny of the lens. It is a white globule, the size
of a tiny pin's head and continued at the back by a pad a little larger,
from which it is separated by a scarcely appreciable crease. The whole
is a sort of nipple swellin