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Show 210 MR. F. E. BEDDARD ON THE OLIGOCH^TE [Mar. 6, sections. The external characters were partly observed by the aid of a lens upon the uninjured worm. The species possesses- and this is quite unusual for an Eudrilid-dorsal pores. This peculiarity is, however, shared by Platydrilus, with which genus I cannot associate the present species. It is not mentioned in Metschaina suctoria. The setae are strictly paired, and do not appear to differ in size anywhere. The male and female pores, each of them single, were quite obvious upon segments xiii. and xvii. The clitellum was undeveloped. In the alimentary caned certain characters are to be noted which are useful in defining the species. The gizzard, as is so usually the case in the Euclrilidae, lies in segment v. There are no additional gizzards at the commencement of the intestine, such as occur, for example, in Lybiodrilus. The intestine begins in segment xvi., and the transition between oesophagus and intestine is abrupt. The intestine is of greater calibre than the oesophagus. The development of the modified calciferous glands which characterise this section of the Eudrilidae is very great, and I believe greater than in any species where they have been described. I find that they extend from segment v. to segment xv. inclusive. As to their structure, they would appear to be quite similar to those which I described in some detail a few years back*. In the type species of this genus, the only one known, the calciferous glands are less extensive, ending as they do in segment xii. The anterior septa are much thickened. The first of this series is that separating segments v./vi. The last separates xiii./xiv. The last two of these sej:>ta are not so very strongly developed as those lying in front of them; but they are, nevertheless, distinguishable from those which follow. The last pair of hearts, as in the Eudrilidae generally, but not apparently in M. suctoria t, lie in segment xi. It is, of course, by means of the reproductive system that the genera of Eudrilidae are mainly to be distinguished. And it is for these reasons that I refer this earthworm to the genus Metschaina. Opening on to segment xiii. is a single median spermathecal pouch. This pouch extends back as far as the fifteenth segment, and the last bit of it has very thin walls, thus contrasting with the anterior thicker-walled portion. The pouch, as is generally the case, can really be separated into a terminal atrium which opens on to the exterior and the sac of thinner texture which follows upon this. This spermathecal sac seems to have no communication whatever with the rest of the female reproductive system. In this important point the present genus resembles Eudriloides only amon^ other allied Eudrilids. In front of the spermathecal sac and attached to the front wall of segment xiii. lies the ovary or ovaries. I noted only one. A remarkable fact about this gonad, as compared with the ovaries of at least some other earthworms, is the fact that the ripe or * " Oligochaeta of Eastern Tropical Africa," Quart. J. Micr. Sci. loc. cit. f Michaelsen, Zool. Jahrb. Abth. f. Syst. xviii. 1903, p. 465. |