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Show 216 MR. F. E. BEDDARD ON [Mar. 3, the sperm-sacs and the terminal apparatus, which opens on to the exterior in the xviith segment. The sperm-sacs are in segments xi. and xii., and occupy a considerable space in those segments. They are simple, solid, sac-shaped structures, not racemose in form. The spermiducal glands are paired. Each of them (see text-fig. 37, p. 215) is shortish and rather thick, tapering somewhat towards the tip. The last third of the gland is bent forward and lies above, parallel to and in contact with the anterior section ol the gland. This arrangement occurred on both sides of the body. Each gland is sharply constricted at its opening into a large median bursa propulsoria lying below the ventral nerve-cord. This latter sac, however, presents obvious signs of having been produced by a fusion of two sacs; for posteriorly it is completely double. It is into each of these posterior lobes that the spermiducal glands open. My description of the female apparatus must unfortunately be incomplete. The organs, as already stated, are paired. The spermathecse, near to where they open, have very thick muscular walls; and this region at least is enveloped in a coelomic sac, as is the base of the spermatheca in the species of Par eudrilus (?), with which I deal later in the present communication (see below). How this coelomic sac is otherwise related to the spermatheca and to the receptaculum ovorum 1 am unable to state. The latter organ presents no noteworthy peculiarities, and the oviduct leads from it to the exterior, on the fourteenth segment. On a Species of P a r e u d r il u s . I believe that a number of individuals belonging to this genus, which were collected by Mr. Crossland, may represent a new species. But I am unable to speak with absolute certainty on the matter, since the material was not in good order for investigation, and since the specimens of P. jiajtillata examined by Michaelsen 1 were likewise much softened by evaporation of the alcohol; if the worms upon which I report here are not referable to P. papillata, then the species is unquestionably new. But whether the species be new or not, 1 have something to add to what is known about the structure of this genus. The dimensions of my specimens agree apparently with those given by Michaelsen for his species. The length was some 100 mm. and the diameter about 3 mm. The dark purple colour, turning to yellow below and in the clitellar region, is like that of my Pareudrilus stagnalis. The seta? are closely paired, and I observed a tendency in the neighbourhood of the genital pores for one seta of a pair to be lost or not developed. I do not refer to a mere dropping out; on examining the cuticle, occasionally no pore was to be noticed in the place where such a pore (through which the seta is extruded) should be. The irregularity of this state of affairs 1 " Die Regemviirmer Ost-Afrikas," in Deutsch-Ost-Afrika, p. 11. |