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Show 162 ON A NEW GENUS OF LUMBRICID.E. [Fe0, ^» complicated in the first few segments after the 17th than in the posterior segments of the body ; the proximal end of the muscular duct passes into a somewhat dilated pear-shaped glandular vessel, into which opens the nephridial tubule; in the posterior nephridium (see fig. 6) the nephridial tubule is very short and bent upon itself four times, the four tubes running parallel with each other ; at a point about opposite to the glandular vesicle the tubule perforates the mesentery and reaches the interior of the segment lying in front of that which contains the distal part of the organ ; here it ends almost immediately in the nephridial funnel, which is very large and conspicuous ; instead of being a simple funnel-shaped expansion, as in tbe majority of Earthworms and in the anterior nephridia of this species, this region of the nephridium forms an elongated folded membrane apparently closely agreeing with the nephridial funnel of Aniens1; this membrane is composed of the ordinary columnar ciliated cells. Reproductive Organs.-There are two pairs of vesicula seminales, situated in segments 11 and 12; each of these bodies is somewhat kidney-shaped and flattened laterally ; the membrane covering the vesiculae is continued over the funnels of the vasa deferentia which open into the same segments. The true testes wyere conspicuous in a young specimen which I investigated by means of transverse sections. I traced back the vasa deferentia, as an excessively fine tube, as far hack as the 18th segment, where it appears to open close to the ventral median line. I could not, however, detect the actual orifices of the vasa deferentia. Prostate glands appear to be entirely absent, as in many (e.g. Urochata, Microchata) of Perrier's Intraclitellians; this group, however, cannot be distinguished by the absence of prostate glands, which are present in Eudrilus, 3/egascolex, and Typhaus. The ovaries are situated in the usual position in segment 13 ; they are small digitate glands. The oviducts open by expanded funnels into the 13th segment which are placed close to the nerve-cord ; their ducts perforate tbe mesentery and open on to the exterior in the 14th segment. I did not, however, observe tbe actual orifice, which must be well within the ventral pairs of setas, if not actually unpaired and median. Spermatheca.-I opened one or two mature individuals and failed to find these organs ; they are, however, usually present to the number of a single pair in the seventh segment. Each spermatheca is a simple, spherical, or pear-shaped pouch without any diverticulum ; it opens exactly in front of the nephridium of the same segment. It appeared to mc at first that this Earthworm might possibly belong to the genus Anteus, E. P. 2 Perrier's description of the genus is not very complete, as it necessarily depended upon a unique example which could be only partially dissected. 1 Perrier, Nouv. Arch. d. Mus. t. viii. pl. i. fig. 14. 2 "Reeherches," &c. Nouv. Arch. d. Mus. t. viii. p 49. |