138 
QUEEN ORGANS. 
millet. On the outside it is densely coated with 
tracheae, which interlace so thickly that they give 
it a white silvery appearance. Leuckart says these 
tracheae only lie on the surface, and can easily be 
removed, or pealed off, and then expose the mem- 
brane of the spermatheca. The tube connecting the 
spermatheca {d) with the vagina (e) is provided 
with muscles, by means of which it can be opened 
or closed for allowing or preventing the passage of 
the spermatozoa. These powerful and complicated 
muscles, discovered by Leuckart ( 93 ) in 1858, and 
which were also seen by Siebold (153), are situated 
very near the connexion of the spermatheca with the 
tube ; they gird and bind it as with a thick ring form- 
ing a swelling, so that when they come into operation 
the duct may be opened or closed, and thus allow the 
spermatozoa to pass, or to keep them back in the 
spermatheca (Leuckart). On the outside of the sper- 
matheca we find two glands, which pass down the 
opposite sides, meeting together and forming a junc- 
tion near the spermathecal duct, which the tubes of 
the glands enter. These glands are called appendicular., 
and their cells secrete a liquid which mixes with the 
spermatozoa and preserves their vitality unchanged for 
a very long period. It is close to the opening of these 
tubes into the spermathecal duct that the valvular 
muscles are situated. 
Siebold and Leuckart both found that if the 
queen is unimpregnated the spermatheca contains 
no traces of spermatozoa, and only a clear fluid, 
which is supplied by the appendicular glands and 
