| OCR Text |
Show 350 MR. E. E. BEDDARD ON EARTHWORMS [Apr. 16, spermatozoa safe inside. In having this open end the spermatophore of Stuhlmannia agrees with the spermatophores of all (?) other Oligocholia. The walls of the spermatophore behind the thickenings at the neck are thin; their constitution suggests that they are net hardened in the specimens which I have examined. The walls are of a granular appearance, being compacted entirely of smaller and larger, more or less obvious, granules, some of which are more, and others hardly at all, stained by borax-carmine. The spermatozoa within the spermatophore closely till the case, and for the far greater part, if not entirely, lie with their long axes parallel to the long axis of the sac. At the head-end, but after the beaklike process in which the spermatophore terminates in frout, there are a quantity of greenish-black granules imbedded in tbe walls of the spermathecal sac. I have always seen these pigmented granules in the spermatophores, and with equal constancy at the head part and nowhere else. The point is of some little importance, as will be seen presently. Although the interior of the spermathecal sac is densely packed with spermatozoa, they do not protrude anywhere through its walls. In this characteristic the spermatophore of Stuhlmannia is more like those of the Lumbricida? than those of the Tubificida1, or its near ally Polytoreutus. Its soft and collapsible looking walls are, however, different from the hard chitinous cases of the spermatophores of Lumbricus, Criodrilus, Alma, and Bothrioneuron. It may, however, on looking back at its various characters, be regarded as intermediate in form and structure between the two types of spermatophores which I have briefly detailed above. The question now arises,- Is the wall of the spermatophore formed out of materials provided by the spermathecal sac or does this material, as it does at least to some extent in Tubifex and its allies, reach the interior of the spermathecal from some other source, such as the spermiducal glands ? It seems to m e that the evidence, as I read it, points to a double origin for the material of the walls of the spermatophores. I have already briefly called attention to the granular and apparently soft walls of the spermatophore. An examination with high powers of the microscope shows that among the irregular granules of which the wall is mainly composed behind the neck are bodies which seem to be of the nature of nuclei. 1 cannot in fact distinguish them from the nuclei of the elongated and irregularly shaped cells of the lining membrane of the spermathecal sac. The size, general shape, and reaction to the staining reagent were identical in both cases, while the cells of the inside of the spermathecal sac were evidently undergoing some breaking up. I may remark at this point, that some observations of Dr. Michaelsen support this interpretation of the characters of the wall of the spermatophore. Dr. Michaelsen L noticed constantly in the spermathecal sac of 1 " Beschreibung der von Jlerrn Dr. Fr. Stuhlmann auf Sausibar und dem gegenuberliegenden Festlande gesammelteu Terricolen." JB. Hamb. wiss. Anst. ix. p. 27. |
