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BRITISH ENTOMOSTRACA. 
mass which is lodged in the neck, and take its place. 
When the glutinous mass is expelled, this granular sub- 
stance continues to swell still more, till at last it expels the 
second substance, or the zoosperms, also. As soon as the 
glutinous matter touches the water, it coagulates, and as 
it continues to flow out, it leaves a canal in the centre of 
the part already expelled and coagulated, which gradually 
becomes lengthened and somewhat undulated. When all 
the glutinous matter has escaped, the zoosperms follow im- 
mediately, and pass through the canal in the coagulated 
part, so that by the time they reach the end of this sort of 
canal, they are close to the vulva. 
“ From all this,” says Siebold,* “it appears — 1st. That 
the male does not accomplish a true coition. 2dly. He 
attaches to the female, during copulation, a tube filled with 
spermatic liquor. 3d. This spermatic tube contains, be- 
side the zoosperms, two substances, of which one (the 
expulsive matter) swells by the influence of the water, and 
chases out the whole contents of the tube. The other 
substance (the glutinous matter) coagulates in the water, 
leaving in the middle of the mass a canal, by which the 
zoosperms arrive at the vulva. 4th. The zoosperms, situated 
in the neighbourhood of the vulva, penetrate in a manner 
as yet unknown beneath the operculum vulvse, and pro- 
bably in this manner fecundate the eggs, which some time 
later quit the sexual opening of the female. 5th. One 
and the same female is often covered with spermatic tubes 
at short intervals by different males. 6th. One and the 
same male appears able to furnish more than one single 
tube from its single sexual organ.” 
These observations of M. Siebold are very curious and 
highly interesting ; they appear to have been made with 
much care : but I am not aware of their having ever been 
confirmed by any succeeding naturalist. 
Jurine distinctly and with truth asserts, that the three 
species which Muller makes, the Cyclops caruleus , rubens , 
* Loc. cit., p. 37. 
