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Show 216 MR. F. E. BEDDARD ON NEW EARTHWORMS. [Mar. 19, The spermiducal glands are tubular in form and of fair thickness ; there is a narrow terminal duct. The glands were bent into an S-shape, and did not extend beyond their segment. The penial setae are not particularly long. They are regularly curved like a bow. There were four of them in each bundle that I examined-two fully mature and two immature. The end of the seta is abruptly truncated, looking very much as if it had been broken off short. There can, however, be no question of such an accident, as all the setae presented the same appearance. The free end of the seta, perhaps one-third of its entire length, is ornamented by transverse ridges, which are apparent at the edges as notches. Hab. St. 99, Magellan Straits, Elizabeth Isl., under cow-dung. (4) Acanthodrilus minutus, n. sp. Of this species, again, I have only discovered a single specimen in the collection. I have been obliged, therefore, to exercise some care in m y dissection of it. It is of a pale brown colour in alcohol, being apparently without any integumental pigment. On a superficial inspection it might easily be mistaken for a small example of Acanthodrilus bovei. The worm measures 29 mm., its diameter is 3 mm.; the number of segments 70. It is therefore, with the exception of the Australian Acanthodrilus macleayi (27 mm.), the smallest Acanthodrilus known. The prostomium is continued by furrows o»er the buccal segment. The setae are strictly paired. In smaller immature specimens, but with more segments, the setae were seen to diverge from each other posteriorly as in A. platyurus &c. The clitellum occupies segments xiii.-xvii. The gizzard is large for so small an earthworm, being 2-5 mm. long by 2 m m . broad. The intestine begins in segment xvii. None of the septa appear to be specially thickened ; but those in the neighbourhood of the generative organs are, as is the rule, somewhat more obvious than the others. Tbe testes and sperm-ducts are, as is often the case with the Acanthodrilus of America, single-that is, there are only one pair of each. The sperm-sacs, racemose and of large size, lie in segment xi. The spermiducal glands are thick but not ver}^ long; they are confined to their own segment. It is noteworthy that the posterior pair are distinctly smaller than the anterior pair, and less coiled. I have observed the same commencing disappearance (?) of one of the two pairs of glands in Acanthodrilus schmardce. The penial setae are long and recurved at the end iu a crozier-like fashion, which is so common in the genital setae of these earthworms. The extremity is expanded and thin, but not ornamented- two in each bundle. |