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Show 1892.] NEW SPECIES OF EARTHWORMS. 151 pair to each " segment " and that has disappeared. It seems to me that we can just as readily explain the apparent anomaly of the nephridiopores being in the middle of the space between two septa by a reference to other genera in which the areas of attachment of septa have shifted from their original position, as I have mentioned in M. belli. Rosa notes it in Hormoyaster1 and Beddard has referred to a similar partial shift of the septa in Libyodrilus 2. With regard to the papillae which exist on the 25th annulus (" segment" of Michaelsen) in K. madagascariensis and on the 26th in K. longus, the suggested modification of enumeration brings each to somite xvi. Michaelsen refers to them as carrying the apertures of the sperm-ducts ; but as he saw no sperm-duct it is quite as probable that they are independent copulatory structures, similar to those I have described in the two species of Microchceta. The interpretation which he gave to them, however, is quite natural, and I myself, till I cut sections through them, presumed that they were the indications of the spermducal pores, and we, as I have mentioned, know of no other instance (except certain papillae in Perichceta, sp., whose structure is unknown) of such organs independent of the sperm-ducts. According to m y view, then, the genus Kynotus is not so aberrant as Michaelsen believes. The genus is a near ally of Microchceta, if, indeed, it be not identical with it, the link between it and M. rappi (the " type" of the genus) being provided by the new species described in the present paper; and were it not for the very close agreement between these species and the two earlier known species of Microchceta (especially in regard to calciferous gland, " hearts," doubling of dorsal vessel, extent of clitellum, position of nephridiopore), I should have referred them to Michaelsen's genus. EXPLANATION OF PLATES VII. & VIII. Figures 1 to 4 illustrate the anatomy of Plutellus perrieri. Fig. 1. View of the ventral surface of the anterior end of the worm, showing the arrangement of the chajtas (the dorsalmost on each side not being visible), the male pores (3)> the extent of the clitellum. Be., protruded buccal cavity. 2. Diagrammatic view of a portion of the body-wall, extending from the mid-ventral line (M. V.) to mid-dorsal line (M.D.). The chaetae (1,2,3,4) have the true relative spacing; neph.o., nephridiopores; spth.p., spermathecal pores. 3. Semidiagrammatic view of a sagittal section through the first twenty segments: parts represented as cut through are drawn from the actual section; organs lying beyond these cut surfaces are put in from other sections. The dotted lines on the dorsal surface indicate the boundaries of somites-in the actual sections they are not present. The septa are represented black, in order that their course may be the more readily followed. Buc, buccal cavity ; cer., brain ; ci.ro., ciliated rosette ; circ, circular muscles of the body-wall; Comm., the peripharyngeal nerve commissure ; gang'., the subpharyngeal or first ventral ganglion ; gen.d., the " genital duct"; giz., gizzard ; lg., longitudinal muscles of the 1 " Sulla strutt. d. Hormogaster reclii," M e m . d. R. Accad. d. Sci. d. Torino, ser. 2, vol. xxxix. 2 " O n the Structure of an Earthworm allied to Nemertodrilus," Q. J. M . So. xxxii. p. 546. |