15151 I IMI 1ATOMOSTK U \ 



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 till- 

 second substance, or the zoosperms, also. As soon as the 

 glutinous matter touches the water, it coagulates, and a> 

 it continues to flow out, it leaves a canal in the centre of 

 tlu; 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 appear.-, 1st. Thai 

 the male does not accomplish a true coition. 2 dry. Me 

 attaches to the female, during copulation, a tube tilled with 

 spermatic liquor. 3d. This spermatic tube contains, be- 

 side the zoosperms, two substances, of which one (tli. 

 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 tin- water, 

 leaving in the middle of the mass a canal, by which the 

 /oosperms arrive at the vulva. 4th. The zoosperms, situated 

 in tin- neighbourhood of the vulva, penetrate in a manner 

 as yet unknown beneath the operculum vulva 4 , and pro- 

 bably in this manner fecundate the eggs, which some time 

 later quit the sexual opening of the female. r>th. One 

 and the same female is often covered with spermatic tubes 

 at short intervals by diH'ereut males. (Hit. One and the 

 same male appears able to furnish more than one single 1 

 tube from its single sexual organ." 



These observations of M . Siebold are \ery curious and 

 highlv interesting; they appear to ha\e been made with 

 much care : but I am not aware of their having ever been 

 confirmed by any succeeding naturalist. 



.lurinc distinctly and with truth asserts, thai the tlnv< 

 \\hicli Muller makes, the ('//</(>/>* candeua, ////"//*. 



l,u. :;/" 



