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Show 346 MR. F. E. BEDDARD ON EARTHWORMS [Apr. 16, to be like those of T. rivulorum (though he enters into no detail in the matter), spermatophores with sharply marked-off heads are not figured, the utmost being an oval swelling at that end of the spermatophore. The one positive fact, however, seems to be of more value than these negative discoveries. Prof. Lankester does not assert that the spermatophores are actually formed in the sperma-thecffi : he is of opinion that while the epithelium of those pouches " furnishes a secretion which occupies part of its cavity and in all probability also assists as a cementing material in the formation of the sperm-ropes," it is probable " that the bulk of the cementing material is introduced into them with the spermatozoa from the male organs of another worm." It is mainly the moulding and hardening which, according to Lankester, is accomplished in the spermatheca. On the other hand, Yejdovsky' leans towards the view that the axial core of the spermatophore is the result of the activity of the spermiducal glands in the Tubificiche, while the transparent sheath is a product of the epithelium of the spermatheca?- a view mainly based upon the fact that immature spermatophores without the outer sheath are found in the spermatheca?, and that a secretion enveloping and binding together the individual spermatozoa has been detected in the spermiducal glands. Vejdovsky would thus divide the labour of producing the spermatophores between the terminal portion of the male efferent apparatus and tbe spermatheca?; but would assign the most characteristic and important part of the spermatophore to the activity of the spermathecal epithelium. I do not venture to dispute this view, as I have no new facts to urge either in its favour or against it; but I may point out that any actual secretion of the case of the spermatophore by the spermathecal epithelium has not been described. It is true that Nasse 2 has stated that during the epoch of sexual maturity the epithelium of the spermatheca^ undergoes a change and partly breaks down into or secretes a fluid substauce, which he compares in its nature to the spermatophore-case. Ou the other hand, the spermatheca? of many earthworms show the same features at the time of ripeness, and in them there is no question, apparently, that the spermatophores are not formed in the spermatheca'. Vejdovsky considers this as " hoc-fast wahrscheinlich "; but adds that the spermatophores of Limnodrilus hoffimcisteri and of L. cla-paredianus might settle the question, as their spermatheca? possess glandular cells which are coloured with a granular pigment. The-spermatophore of the latter species has been since described by Stole ; but it is not apparent from his figures that there is any pigment in the hyaline sheath of the structure. Neither does Vejdovsky again allude to the matter in his later account of the spermatophores of Tubifex blanchardi. In the meantime therefore the actual source of the materials employed in the manufacture of the spermatophores in those worms cannot be entirely traced. 1 System u. Morph. d. Oligochaeten, Prag, 1S84, p. 153. '' Beitrage zur Anatomie der Tubificiden, Inaug.-Diss., Bonn, 1882. |