hich my
observations have supplied. To obtain a good idea of the internal
distribution, we must split the stalk lengthwise, in the winter, when
the provisions have long been consumed and when the larvae are wrapped
in their cocoons. We then see that, at regular intervals, the case
becomes slightly narrower; and in each of the necks thus formed a
circular disk is fixed, a partition one or two millimetres thick.
(.039 to.079 inch.--Translator's Note.) The rooms separated by these
partitions form so many little barrels or kegs, each compactly filled
with a reddish, transparent cocoon, through which the larva shows,
bent into a fish-hook. The whole suggests a string of rough, oval amber
beads, touching at their amputated ends.

In this string of cocoons, which is the oldest, which the youngest? The
oldest is obviously the bottom one, the one whose cell was the first
built; the youngest is the one at the top of the row, the one in the
cell last built. The oldest of the larvae starts the pile, down at the
bottom of the gallery; the latest arrival ends it at the top; and those
in between follow upon one another, according to age, from base to apex.

Let us next observe that there is no room in the shaft for two Osmiae at
a time on the same level, for each cocoon fills up the storey, the keg
that belongs to it, without leaving any vacant space; let us also remark
that, when they attain the stage of perfection, the Osmiae must all
emerge from the shaft by the only orifice which the bramble-stem
boasts, the orifice at the top. There is here but one obstacle, easy
to overcome: a plug of glued pith, of which the insect's mandibles make
short work. Down below, the stalk offers no ready outlet; besides, it is
prolonged underground indefinitely by the roots. Everywhere else is the
ligneous fence, generally too hard and thick to break through. It is
inevitable therefore that all the Osmiae, when the time comes to quit
their dwelling, should go out by the top; and, as the narrowness of
the shaft bars the passage of the preceding insect as long as the next
insect, the one above it, remains in position, the removal must begin at
the top, extend from cell to cell and end at the bottom. Consequently,
the order of exit is the converse to the order of birth: the younger
Osmiae leave the nest first, their elders leave it last.

The oldest, that is to say, the bottom one, was the first to finish her
supply of honey and to spin her cocoon. Tak