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Show 166 MR. F. E. BEDDARD ON WORMS [Feb. 16, smallness of the atria and the spermathecae as a characteristic of the species. Each spermatheca consists of a globular portion communicating with the exterior by a narrow duct, to which is appended a small diverticulum consisting also of a swollen terminal portion and of a narrow duct. PERICHCETA MORRISI, n. sp. I name this species, of which I obtained several living examples from Kew, after Mr. Morris, Assistant Director of the Royal Gardens. Three or four specimens were forwarded to me, of which only one was sexually mature; the following description is based upon that specimen. The species comes from Penang. The accompanying coloured sketch by Mr. Smit (Plate IX. fig. I) represents the natural colours of the worm and shows its distinctness from Perichceta sinensis, with which species, however, it cannot be confounded, as will be seen in the course of the following description. The worms during life protruded the buccal cavity, as apparently all species of Perichceta do. The length of the specimen (after preservation in weak, followed strong, alcohol) is 52 m m . ; the number of segments in the body is 93. The setce, as in other species, form continuous rows. The clitellum begins abruptly with the commencement of segment xiv., but does not terminate exactly at the posterior boundary of segment xvi.; the glandular substance ends at the level of the setae which are present on the last segment of the clitellum, as in Perichceta bermudensis (see p. 160) ; the setae of this segment, as in the species with which I have compared Perichceta morrisi in this particular, are only present upon the ventral surface. The oviducal pore occupies the usual position. The atrial pores open on to the xviiith segment, and are not separated by a very wide interval; they are in the line of setae, but the setae cease for a short space on either side of each pore. The spermathecal pores lie between segments v./vi. and vi./vii. There are no papillce in the neighbourhood of the male pores, although on a subsequent dissection of the worm I noticed some minute white glands in the xviiith segment. Papillae, however, are present upon certain of the anterior segments in the neighbourhood of the spermathecal apertures. Upon each of segments vii. and viii. is a single circular disk occupying the median ventral line of the segment and lying just in front of the circle of setae belonging to the segment. The gizzard lies in segments viii.-x., the mesenteries which should divide those segments being absent. The usual pair of caeca are present. The oesophagus in segments x.-xiv. is much thickened and of a whitish appearance. This region doubtless corresponds to the calciferous glands of other Earthworms, which do not appear to be developed as distinct pouches in the genus Perichceta. |