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Show 348 ON EARTHWORMS FROM SOUTH AFBICA. [Mar. 16, xii./xiii. It is rather less obvious than the male pore, which is between segments xvii. and xviii. The latter is more conspicuous on account of the fact that the actual pore lies upon the summit of an elevated tract of the skin. The position of the generative apertures and their general appearance presents the closest likeness to the West African Lyhlodrllus, from which worm the elongated spermiducal glands appearing through the skin serve to differentiate the present species even before dissection. The alimentary canal shows characters that are typically Eudrihd. In each of segments x. and xi. is a single median unpaired calciferous gland, which is of a deep red colour and nearly globular in outline. In segment xiii. are the paired calciferous glands, which are white in colour and not large. Each is curved into rather more than a semicircle and the margin is indented. The large Intestine begins in segment xiv. The gizzards, as in other allied forms, are some way down the intestine. There are three of them lying in segments xviii., xix., xx.; there is nothing peculiar about them except the position, which is not unusual among the Eudrilidae, as already mentioned. This earthworm bas " hearts " in each of segments vii.-xi. As in so many Eudrilids, the funnels of the sperm-ducts, of which there are two pairs in segments x. and xi., are followed by a dilated sac which in the present species is egg-shaped. The funnels themselves, which look backwards (so far as I could make out), appear to be plunged in the interior of the sperm-sacs, of which there are likewise two pairs ; these latter organs depend from the anterior wall of segments xi. and xii. and are long and tongue-shaped, being flattened somewhat and wider towards the blind extremities. The testes I did not see. The spermiducal glands are very conspicuous, and, as already mentioned, are visible through the translucent walls before the body is cut open. The two tubes have the nacreous appearance which is so usual with those glands in the present family ; they are somewhat spirally twisted in their course, and therefore do not reach so far back in the body as would be the case did they lie straight. Each of the glands measures 22 m m . in length; the two unite just at their opening on to the exterior by a short terminal bursa. The sperm-ducts open into them some way before their termination. I could find no penial setce. The female reproductive organs conform generally to the plan characteristic of the family, and are to the full as complicated as in any other genus. The orifice already referred to leads into a sac which lies beneath the nerve-cord and extends back for a distance of 5*5 m m . It has a wide cavity, wdiich in the specimen that I dissected appeared to be empty. Into this sac, which is the sperma-thecal sac, opens on either side a tube of some length which is disposed in a circle. This tube is at first wide and sacculated. After a course of about 10 m m . it suddenly narrows, and the lumen, at first wide in proportion to the thickness of the walls, becomes much constricted. This narrow tube then dilates to form what |
