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Show 1892.] AN ABNORMAL EARTHWORM. 187 Eisen ' in Eclipidrilus has described three pairs of ovaries situated on segments 9, 10, and 11 ; this statement is challenged by Vejdovkya, who maintains that the Oligochseta possess only a single pair of ovaries which are never found on the segments behind the oviducts (see fig. 1, ov.3-ov.7). In like manner the last-named authority would throw doubt on Lankester's3 description of the two pairs of ovaries present in Chcetogaster. A m o n g the other genera of the Oligochaeta, so far as I a m aware, only one pair of ovaries is developed ; this in the Lumbricomorpha is usually situated on the 13th somite. But, as has been just pointed out, at least eight genera may possess more than one pair, and, further, in many forms the ovaries are developed on segments other than the 13th. The following table shows the variation in the position of the ovaries in those forms that possess two or more pairs of ovaries:- Somites Acanthodrilus Eclipidrilus Eudrilus Lumbricus terrestris (?her-culeus) (normal) L. herculeus (Benham) .. L. purpureus and L. tumi-dus (Bergh) Allolobophora, sp.? (ab- Perionyx (two pairs "1 varying from 9-16). j Phreodrilus 9. X ««- 10. X ... n. X ... 1 ...! x ... j ... 12. X X X X X 13. X X X X X X X X 14. lfi X? X X X X 16. X 17. X 18. X From this table it will be seen that within the limits of the Lumbricomorpha the ovaries are found to vary in position from the 9th to the 18th somite, the maximum number thus far known to be developed being seven pairs. In front of these we find in m y specimen the two typical pairs of testes developed on segments 10 and 11. As these are without doubt the serial homologues of the ovaries, the genital glands in this worm extend from the 10th to the 18th somites. The genital glands are developed from and under cover of the peritoneal epithelium, on the posterior face of the mesenteries of the genital somites. A.nd when we consider that the mesenteries, from which the germinal epithelium arises, are present for each segment of the body, and, further, that in most of its organs the worm exhibits a marked metamerism, it at once suggests itself that in those forms 1 " Eclipidrilidae and their Anatomy," Nov. Act. R. Soc. Sci. Upsala, vol. xi. (1881). - Syst. d. Oligochaeten, p. 144: Prague, 1884. 3 "The Sexual Form of Chcetogaster," Q. J. M . S. n. s> vol. ix. (1869) p. 272, |