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Show 380 MR. F. E. BEDDARD ON THE [June 18, 8. PERICH/ETA INTERMEDIA, n. sp. The prostomium does not divide the buccal segment. The setee form a nearly complete ring round each segment, failing for a short space in the mid-dorsal and mid-ventral lines. Dorsal pores absent. Clitellum 1 Alimentary tract. The gizzard lies in segment v. ; it is small and inconspicuous. The calciferous glands present the appearance of dilatations of the oesophagus in segments x. and xi. Nephridia are a series of paired tubes, opening by laterally placed orifices. Sperm-sacs in segments ix., x., xi., xii. Vasa deferentia open on to segments x. and xi. The atrium is tubular as in Acanthodrilus ; it is not furnished with a sac of penial setse ; the vas deferens of each side appears to open in common with it. Intersegmental septa separating segments viii.-xv. very greatly thickened. Receptacula ovorum are conspicuous on the anterior septum of segment xiv. Spermathecce four pairs in segments v.-viii.; each is furnished with a minute diverticulum lying to the inner side. 9. PERICHEETA ANTARCTICA (Baird). Magascolex (Pericheeta) antarctica, Baird, Journ. Linn. Soc. vol. xi. p. 96. P. antarctica, Beddard, Proc. Roy. Soc. Edinb. vol. xiv. p. 175. Genus NEODRILUS, F. E. B. Neodrilus, F. E. Beddard, P. R. Soc. Edinb. vol. xiv. p. 157. Closely resembling Acanthodrilus, but differing in the presence of only a single pair of tubular atria in segment xvii. and a single pair of spermathecse in viii. Each spermatheca is furnished with a very large diverticulum lying in the anterior segment. Nephridia paired and alternate in position. 10. NEODRILUS MONOCYSTIS, F. E. B. N. monocystis, F. E. Beddard, P. R. Soc. Edinb. vol. xiv. p. 157. RHODODRILUS, nov. gen. Setse in 8 series. Clitellum occupying segments xiv.-xvii.; atria tubular; penial setse present; vasa deferentia opening on to the exterior on the same segment (xvii.), but independently of atria ; gizzard present. This genus comes near to Cryptodrilus and Megascolides, and possibly includes some species described by Fletcher (5) under these two genera. In the former genus I place those species with lobate atria like those of Pericheeta; Megascolides includes species which have tubular atria, no penial setse, and a clitellum extending as far as segment xx. or further. |