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Show 238 ME. F. E. BEDDAED ON NEW EAETHWOBMS. [Mar. 19, individuals the colour was much more sombre and there was hardly any indication of the white seta areas. The largest individual which was measured had a length of 52 mm., a diameter of 3'5 mm., number of segments 60. This was one of the more darkly coloured individuals, which might perhaps be regarded on account of this slight difference as a variety. A more typical specimen (as regards colour) was 32 m m . by 3 mm., with 50 segments. But there is a considerable range in size. The prostomium completely divides the buccal segment. The setae are not strictly paired, but the setae of the lateral couples are farther away from each other than are those of the ventral. The latter hardly come nearer to each other on the segments in the neighbourhood of the xviith ; the approximation is not marked, as in some species. The clitellum occupies segments xiii.-xvi., half only of the first and last. The dorsal pores are present and appear to begin on the clitellum. The gizzard is large compared to tbe size of the worm ; in the smaller of the two individuals whose measurements are given above it was in segments vi., vii. In a specimen sectioned longitudinally the greater part of the gizzard was seen to lie in vi. The intestine begins in xvii. Behind the gizzard are a number of septa which, though not greatly thickened, are stouter than those which follow them. The last of these bounds segment xiv. anteriorlv. The last heart is, as usual, in segment xii. The nephridia commence in segment v. There is only a single pair of testes and funnels in segment x. The sperm-sacs are large and racemose and lie in segment xi. There is also a pair in ix. which are a good deal less obvious. The spermiducal glands are stout and of the tubular character invariably found in this genus. The muscular duct leading to the exterior is moderately long. The penial setae (two in a sac) are longish (2-5 mm.) and quite unornamented. The free extremity gradually tapers to a point. The sac of setae opens in common with the spermiducal gland. The sperm-duct opens just separately on to exterior. The spermathecae are in ix. The diverticulum is nearly as long as the pouch, but has a mulberry-like appearance. In sections the diverticulum shows much the same structure that I have described above in ill. gracilis. The same locality also produced three specimens of a small Microscolex which I was at first inclined to regard as a distinct species. I consider, however, that it is merely a small variety of Microscolex diversicolor. The total length of the largest individual is 30 mm., the diameter 2 mm., number of segments 100. It is evidently therefore a more slender worm than the type. The setae appear to be a little more paired than in the type. Hab. St. 41, Valdivia, Estancilla. St. 48, Corral. St. 38, Valdivia. St. 36, Valdivia. St. 46, Corral. |
