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Show 1901.] FROM BRITISH EAST AFRICA. 363 no material for comment. They are quite normal in position and structure. The spermathecce are rather peculiar. There are two pairs, which lie in segments viii., ix. Each consists of an oval sac with a simple lining of cells and a very thin muscular wall; this communicates with the exterior by an extremely long slender duct, which is much longer than the pouch itself, and is so thin as to hardly exceed the dimensions of the sperm-duct. There is no trace of a diverticulum. On the left-hand side of segment viii. there were, in the single example of the species which I have had for investigation, two spermatheca?, each with its separate long duct. The two pouches appeared to communicate. It is clear that the spermatheca? of the present species closely resemble those of G. tenuis in the length of their ducts. It is plain that the species described in the present communication not only, as already pointed out, bridges over the not very wide gap which lias hitherto separated the twTo genera Gordiodrilus and Nannodrilus, but that it also connects the somewhat extreme Gordiodrilus tenuis with the more " normal" species of the genus. The peculiarities of G. tenuis would seem almost to necessitate its inclusion in a separate genus. The existence of only a single pair of testes and of sperm-ducts and the backward position of the male orifices, together with the curious form of the spermatheca?, are three points which might be regarded as collectively entitling to generic separation. Gordiodrilus papillatus, however, while agreeing with 67. tenuis in the form of the spermatheca?, in the large size of the ventral seta?, and approaching it in the position of the male genital orifices, has the normal pair of testes in each of segments x. and xi. The clitellum, too, is like that of other species, and is not so prolonged as is the clitellum of G. tenuis. The seta?, moreover, do not show throughout the body such a marked discrepancy of size as is exhibited by the species G. tenuis. I shall conclude with a brief definition of GORDIODRILUS PAPILLATUS. n. sp. Length 63 m m . Seta? of ventral pairs larger. Male pores on xix., xx., and xix./xx. Gizzard absent. Four pairs of genital papilla? on xix., xx., and three median papilla? on xxiv., xxv., xxvi. Testes two pairs. Sperm-ducts open into a muscular bursa. Spermatheca?, two pairs without diverticula and with enormously long and slender duct. IIcd>. Lagos. GORDIODRILUS ROBUSTUS. G. robustus, F. E . Beddard, Ann. Nat. Hist. (6) x. p. 82 ; id. Mon. Olig. 1895, p. 508. G. robustus, Michaelsen, Oligochaata, Das Tierreich, Lief. x. 1900, p. 374. . T w o examples of this species allow of certain additions to the |