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Show 1886.] MR. F. E. BEDDARD ON A LARGE EARTHWORM. 173 of the penial setas agree with those of A. ungulatus as described by Perrier l. The ovaries and oviducts I have been unable to find. There are two pairs of spermathecce situated in segments 8 and 9 ; each consists of a spherical thin-walled sac communicating with the exterior by a long stout-walled duct which is often curved (see figs. 5 and 6, cp) ; at the upper extremity of the duct, where it unites with the sac, it becomes somewhat bulged out on one side, though there is hardly so marked a diverticulum as is figured by Perrier in A. ungulatus 2. A very characteristic and remarkable series of structures now remain to be described, before concluding the account of the generative system. In describing the external characters attention was drawn to the modification of the lowermost pair of setae in segment 8; the ordinary setae, at any rate on one side of the body, have disappeared and are replaced by a conspicuous orifice through which protrude one or more stout long setae, which appear on a naked-eye inspection to be very similar to those which project through the male generative pores. Fig. 5 of PI. X I X . represents the internal structures which correspond to these peculiarly modified setae; the latter are contained in a thin-walled transparent sac (s) precisely as are the genital setae ; on either side of this sac is a long somewbat sausage-shaped glandular body (g.b), which communicates by a slender duct with the orifice through which the setae project on to the exterior. The presence of these glands renders the whole structure more similar still to the male generative pore, except that the "prostates" are paired. These structures were only present on the left side of the body in one specimen; in two others they were only developed ou the right side; in two other specimens both immature, without a clitellum, these structures were entirely absent on both sides of the body; in a sixth specimen, which was also immature, with the clitellum undeveloped and with very minute spermathecae, the bundle of modified setae was plainly visible on both sides of the body, but without its accessory glands; in the seventh specimen, also immature, there was no vestige whatever of these structures ; wherever they were absent the setae of the segment were perfectly normal. I am not aware that any structures of this kind have been described in any other species of the genus or in any other Earthworm ; they appear to be novel to the group. At the same time Perrier figures some structures in A. ungulatus* which may be identical, though the figure and his description are insufficient; the description (p. 92) is as follows:-" Les poches copulatrices sont situees aux anneaux huit et dix. Chacune est munie d'uu lobe poste'rieur, assez petit, et n'a pas d'autre appendice. Dans le neuvieme anneau se voient plusieurs sacs glandulaires, separes par une glande multifide." The details are evidently different from the structures that I have just described, but the similarity of position, between the two spermathecce, renders it possible that they are identical ; in 1 Loc. cit. p. 90, pi. ii. figs. 21, 22. 3 Loc. cit. pi. ii. fig. 20. 3 Loc. cit. pi. ii. fig. 18, x. |
