The Cambridge natural history, Vol. 06 (of 10)Sharp, David
Science
The Cambridge natural history, Vol. 06 (of 10)
Sharp, David
Animals
M. Fabre has succeeded in elucidating the history of _Sitaris humeralis_, a
Cantharid that lives at the expense of bees of the genus _Anthophora_.[143]
The eggs of the _Sitaris_ are deposited in the earth in close proximity to
the entrances to the bees' nests, about August. They are very numerous, a
single female producing, it is believed, upwards of 2000 eggs. In about a
month—towards the end of September—they hatch, producing a tiny triungulin
of black colour; the larvae do not, however, move away, but, without taking
any food, hibernate in a heap, remaining in this state till the following
April or May, when they become active. Although they are close to the
abodes of the bees they do not enter them, but seek to attach themselves
{273}to any hairy object that may come near them, and thus a certain number
of them get on to the bodies of the _Anthophora_ and are carried to its
nest. They attach themselves with equal readiness to any other hairy
Insect, and it is probable that very large numbers perish in consequence of
attaching themselves to the wrong Insects. The bee in question is a species
that nests in the ground and forms cells, in each of which it places honey
and lays an egg, finally closing the receptacle. It is worthy of remark
that in the case of the _Anthophora_ observed by M. Fabre, the male appears
about a month before the female, and it is probable that the vast majority
of the predatory larvae attach themselves to the male, but afterwards seize
a favourable opportunity, transfer themselves to the female, and so get
carried to the cells of the bee. When she deposits an egg on the honey, the
triungulin glides from the body of the bee on to the egg, and remains
perched thereon as on a raft, floating on the honey, and is then shut in by
the bee closing the cell. This remarkable act of slipping on to the egg
cannot be actually witnessed, but the experiments and observations of the
French naturalist leave little room for doubt as to the matter really
happening in the way described. The egg of the bee forms the first
nutriment of the tiny triungulin, which spends about eight days in
consuming its contents; never quitting it, because contact with the
surrounding honey is death to the little creature, which is entirely
unfitted for living thereon. After this the triungulin undergoes a moult
and appears as a very different creature, being now a sort of vesicle with
the spiracles placed near the upper part; so that it is admirably fitted
for floating on the honey (Vol. V. Fig. 86, 10). In about forty days, that
is, towards the middle of July, the honey is consumed, and the vesicular
larva after a few days of repose changes to a pseudo-pupa (11 of the fig.
cited) within the larval skin. After remaining in this state for about a
month, some of the specimens go through the subsequent changes, and appear
as perfect Insects in August or September. The majority delay this
subsequent metamorphosis till the following spring, wintering as
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account