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Show 1895.] MR. F. E. BEDDARD ON NEW EARTHWORMS. 2] 7 The spermathecae have a single rather large tubular to oval diverticulum. Hab. St. 30, Putabla, Valdivia. (5) Acanthodrilus bicinctus, n. sp. Of this species there were two examples from Pictou Island and two from Juan Island. The two latter were rather larger than the former and showed a slight difference in the penial setae, which will be referred to in due course. The length is 42 mm., diameter 3 mm.; number of segments 80. The larger worm from Juan was 55 m m . in length. The colour of the species is a dark purple, passing into an orange-brown on the ventral surface. The colour was darker than in most Acanthodrili. The prostomium is broad, narrower posteriorly where it is continued over the buccal segment for about two-thirds of its leugth. Posteriorly the prostomium bears a dorsal groove which is continued to the end of the buccal segment, and is apt to produce the impression of the prostomium entirely dividing the buccal segment. The clitellum occupies segments xiii.-xvi.: in one specimen it was divided by a median furrow into two halves, each consisting of two segments ; this circumstance suggested the specific name. There are median unpaired genital papillae, extending between the ventral setae on segments xx. and xxi. in one individual, and in another on to the two following segments also. The gizzard is well developed. The reproductive organs are not very different from those of some allied species; I fancy that the gonads are only one pair of testes, and of course one pair of ovaries, but am not quite certain. In any case there is but a single pair of large racemose sperm-sacs in segment xi., as is so general. The spermiducal glands are large and flattened, being coiled several times in one plane ; the two following glands of each side of the body form an almost continuous mass occupying segments xvi.-xx. The narrow muscular duct of the gland arises from about the middle of the coil. It is accompanied by a sac contain-i g two penial setae which are fully mature, and two immature ones. The former are of a particularly bright yellow colour. One is bent like a bow in a regular curve and ends in a sharp point; its distal third is beset with sharp downwardly directed spinelets. The other seta is of quite a different form. To begin with, it is at least quite half as long again as the first and is more flexible; this appears to be shown by the whip-like curvature of tbe distal extremity, which is disposed almost in coils. It terminates in an obtusely pointed extremity. Less than the distal third of this seta is beset with excessively fine spinelets, much finer than in the other seta. There can be no question that both setae are fully mature and they show a dimorphism. A similar dimorphism has been indicated by myself to exist in Acanthodrilus georgianus. It has also been met with elsewhere. In the specimen from Juan |