e at each end, though the free end of the last cell is
rounded off. They are four and a half tenths of an inch long, and a
little over one-third as broad. The bee places them at nearly equal
distances apart, the slight interval between them being filled in with
dirt.

[Illustration: 22. Nest of Ceratina.]

Dr. T. W. Harris states that May 15, 1832, one female laid its eggs in
the hollow of an aster stalk. Three perfect insects were disclosed from
it July 28th. The observations of Mr. Angus, who saw some bees making
their cells May 18th, also confirm this account. The history of our
little upholsterer is thus cleared up. Late in the spring she builds her
cells, fills them with pollen, and lays one or more eggs upon each mass.
Thus in about two months the insect completes its transformations;
within this period passing through the egg, the larva and chrysalid
states, and then, as a bee, living a few days more, if a male; or if a
female, living through the winter. Her life thus spans one year.

The larva (Fig. 23) is longer than that of Megachile, and compared with
that of Xylocopa, the different segments are much more convex, giving a
serrate outline to the back of the worm. The pupa, or chrysalis, we have
found in the cells the last of July. It is white, and three-tenths of an
inch long. It differs from that of the Leaf-cutter bee in having four
spines on the end of the body.

[Illustration: 23. Larva of Ceratina.]

[Illustration: 24. Nest of Tailor Bee.]

In none of the wild bees are the cells constructed with more nicety than
those of our little Ceratina. She bores out with her jaws a long deep
well just the size of her body, and then stretches a thin, delicate
cloth of silk drawn tight as a drum-head across each end of her
chambers, which she then fills with a mixture of pollen and honey.

[Illustration: 25. Tailor Bee.]

Her young are not, in this supposed retreat, entirely free from danger.
The most invidious foes enter and attack the brood. Three species of
Ichneumon flies, two of which belong to the Chalcid family, lay their
eggs within the body of the larva, and emerge from the dried larva and
pupa skins of the bee, often in great numbers. The smallest parasite,
belonging to the genus Anthophorabia, so called from being first known
as a parasite on another bee (Anthophora), is a minute species found
also abundantly in the tight cells of the Leaf-cutter bee.

The interesting habits of the Leaf-cutting, o