Leucopsis' larva while it is in a semifluid
state and deep in the torpor of the nymphosis. The last fortnight in
July and the first fortnight in August are the best times to witness the
repast, which I have seen going on for twelve and fourteen days. Later,
we find nothing in the Mason-bee's cocoon except the Leucopsis' larva,
gloriously fat, and, by its side, a sort of thin, rancid rasher, the
remains of the deceased wet-nurse. Things then remain as they are until
the hot part of the following summer or at least until the end of June.

Then appears the nymph, which teaches us nothing striking; and at last
the perfect insect, whose hatching may be delayed until August. Its exit
from the Mason's fortress has no likeness to the strange method employed
by the Anthrax. Endowed with stout mandibles, the perfect insect splits
the ceiling of its abode by itself without much difficulty. At the
time of its deliverance, the Mason-bees, who work in May, have long
disappeared. The nests on the pebbles are all closed, the provisioning
is finished, the larvae are sleeping in their yellow cocoons. As the
old nests are utilized by the Mason so long as they are not too much
dilapidated, the dome which has just been vacated by the Leucopsis,
now more than a year old, has its other cells occupied by the Bee's
children. There is here, without seeking farther, a fat living for the
Leucopsis' offspring which she well knows how to turn to profit. It
depends but on herself to make the house in which she was born into
the residence of her family. Besides, if she has a fancy for distant
exploration, clay domes abound in the harmas. The inoculation of the
eggs through the walls will begin shortly. Before witnessing this
curious performance, let us examine the needle that is to effect it.

The insect's abdomen is hollowed, at the top, into a furrow that runs up
to the base of the thorax; the end, which is broader and rounded, has a
narrow slit, which seems to divide this region into two. The whole
thing suggests a pulley with a fine groove. When at rest, the
inoculating-needle or ovipositor remains packed in the slit and the
furrow. The delicate instrument thus almost completely encircles the
abdomen. Underneath, on the median line, we see a long, dark-brown
scale, pointed, keel-shaped, fixed by its base to the first abdominal
segment, with its sides prolonged into membranous wings which are
fastened tightly to the insect's flanks. Its function is