A Text-book of Entomology: Including the Anatomy, Physiology, Embryology and Metamorphoses of Insects for Use in Agricultural and Technical Schools and Colleges as Well as by the Working EntomologistPackard, A. S. (Alpheus Spring)
Science
A Text-book of Entomology: Including the Anatomy, Physiology, Embryology and Metamorphoses of Insects for Use in Agricultural and Technical Schools and Colleges as Well as by the Working Entomologist
Packard, A. S. (Alpheus Spring)
Insects
An excellent account of the honey-bee’s sting is given by Cheshire
(Figs. 194, 195). The outermost of the three pairs of stylets
forming the apparatus is the two thick, hairy “palpi” or feelers
(_P_), these being freer from the sting proper than in the
ovipositor of Orthoptera. The sting itself is composed of the two
inner pairs of stylets; one of these pairs is united to form the
sheath (_sh_), while the other pair form the two barbed darts. The
sheath has three uses: first, to open the wound; second, to act as
an intermediate conduit for the poison; and third, to hold in
accurate position the long barbed darts. The sheath does not enclose
the darts as a scabbard, but is cleft down the side presented in
Fig. 194, which is below when the sting points backward. But, says
Cheshire, as the darts move up and down, they would immediately slip
from their position, unless prevented by a mechanical device,
exhibited by _B_ and _C_, giving in cross-section sheath and darts
near the end, and at the middle of the former. “The darts (_d_) are
each grooved through their entire length, while upon the sheath
(_sh_) are fixed two guide rails, each like a prolonged dovetail,
which, fitted into the groove, permits of no other movement than
that directly up and down.” The darts are terminated by ten barbs of
ugly form (_D_, Fig. 194), and much larger than those of the sheath,
and as soon as the latter has established a hold, first one dart and
then the other is driven forward by successive blows. These in turn
are followed by the sheath, when the darts again more deeply plunge,
until the murderous little tool is buried to the hilt. But these
movements are the result of a muscular apparatus yet to be examined,
and which has been dissected away to bring the rigid pieces into
view. The dovetail guides of the sheath are continued far above its
bulbous portion, as we see by _E_, Fig. 195; and along with these
the darts are also prolonged upward, still held to the guides by the
grooved arrangement before explained; but both guides and darts, in
the upper part of their length, curve from each other somewhat like
the arms of a Y, to the points _c_, _c′_ (_A_, Fig. 194), where the
darts make attachment to two levers (_i_, _i′_). The levers (_k_,
_l_ and _k′_, _l′_) are provided with broad muscles, which terminate
by attachment to the lower segments of the abdomen. These, by
contraction, revolve the levers aforesaid round the points _f_,
_f′_, so that, without relative movement of rod and groove, the
points _c_, _c′_ approach each other. The arms of the Y straighten
and shorten, so that the sheath and darts are driven from their
hiding-place together and the thrust is made by which the sheath
produces its incision and fixture. The sides being symmetrical, we
may, for simplicity’s sake, concentrate our attention on one, say
the left in the figure. A muscular contraction of a broad strap
Public-domain text, read in full here on John Shaqi.
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