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Show 306 MR. F. E. BEDDARD ON NEW OR [May IS, deferentia on each side, which were invariably extremely conspicuous; the two vasa deferentia of each side remained perfectly distinct, and could readily be traced as far as the prostatic gland, into which they open. The latter structure is a tubular organ of a nacreous appearance, lying behind the generative orifice, and occupying some five or six segments; it communicates with a large rounded pouch-like structure (figs. 1, 2, b), which overlies the generative pores on either side, by a narrow duct. The prostatic gland is constricted at about the middle of its extent, and it is at this point that the vasa deferentia open into it. M. Perrier has accurately figured the appearance presented by the ' bursa copulatrix' when its upper wall has been removed (loc. cit. pi. ii. figs. 27, 28). I find that the duct of the prostatic gland is continuous with the curved penis (woodcut fig. 2), while the rounded pad (c) which lies behind the penis receives the duct of a peculiar glandular body (a), which is either horseshoe-shaped as in fig. 2 or Y-shaped as in fig. 1. This glandular appendix has been referred to by Perrier, who did not, however, succeed in making out its relations with the bursa copulatrix ; neither has M. Perrier figured or described the termination of the prostatic duct in the penis. 4. ADDITIONAL NOTE ON MICROCH^ETA RAPPII, F. E. B. Since my paper on the structure of this Worm was communicated to the Society, Mr. Benham has published a careful and detailed account of its anatomy. The description of the female generative apparatus which Mr. Benham gives1 agrees in the main with my own description, which I have left unaltered in the paper. A structure which I identified with the oviduct-a pair of ciliated funnels on the posterior wall of segment 12-has appeared to Mr. Benham not to be really an oviduct but to be related to a glandular structure on the anterior septum of segment 12, possibly serving as tbe excretory duct of its products. On the other hand, the structure described by myself as an ovary, lying in the segment behind that which contains the presumed oviduct (Trans. Zool. Soc. vol. xii. pt. 3, pi. xv. fig. 4, o), is also identified as such by Mr. Benham. I am now inclined to think that both Mr. Benham and myself were wrong in that identification, and that the supposed ovary really corresponds to what has been termed by Bergh2 the recepta-culum ovorum. In the first place, Mr. Benham remarks that the ova which completely filled this supposed ovary exhibited no gradation in size among themselves such as is to be seen in the ova of Lumbricus ; in tbe second place, I have observed this structure in another example of the worm, recently received at the Gardens from the Rev. G. H. R. Fisk, where it was entirely devoid of ova. I cut a careful series of sections through the 'ovary' and oviduct, and could 1 Quart. Journ. Micr. Sci. 1886, p. 279, pi. xvi. figs. 7, 8, 14. 2 Zool. Anzeiger, no. 220, p. 232. |