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Show 340 MR. F. E. BEDDARD ON EARTHWORMS [Mar. 16, chitinous-looking case, which I take to be a spermatophore. It is important to notice the apparent existence of spermatophores in this species, as they are structures which, apart from the Lumbri-cidae, are not common among earthworms. The diverticula as usual contain masses of spermatozoa, there being none in the spermatheca itself. These are firmly attached to the glandular walls of the diverticula: these glandular walls are composed of a layer of granular, slightly staining cells, whose limits are not definable ; the lumen which the cells leave is but narrow. I constantly found that of the two diverticula of each spermatheca, one lay in the segment containing the pouch, and the other in the segment in front. The sperm-sacs are in segments ix.-xii. inclusive. I did not observe the shape of the penial setce, but ascertained their presence. (3) Acanthodrilus arenarius, n. sp. Of this species Mr. Pureed collected 23 specimens " in wet sand under stones on the edge of a small vley (lake), situated at the beginning of the sand-dunes due east from Wynberg station.'' This is a small slender species rather over two inches in length, with a very prominent swollen clitellum. The measurement of an average individual was 65 m m. The anterior end of the living worms is darkly pigmented. The prostomium is incomplete. The setce are more closely paired ventrally than dorsally. The clitellum occupies a portion of segment xiii. and all of segments xiv.-xvi. On the clitellum the nephridiopores are obvious, lying in front of seta 3. This species bas a number of genital papillce; the numbers vary in different individuals. In the most fully developed there was a single median papilla upon segments viii.-x., xviii.-xxiii.; and in addition to these unpaired papillae, paired papdlae upon each of segments xvii.-xix. On xviii. I found two pairs of these paired papillae situated one in front of the other. These pairs were on a level with the generative orifices. The papillae have a cup-like appearance. In sections, the epithelium of which they are composed is seen to be glandular like that of the clitellum but not so deep. The alimentary canal has a fairly developed gizzard. The oesophagus alters its character in the xiiith segment, becoming rather wider and thinner-walled. In front the epithelial walls are folded, the only trace of calciferous glands which the worm possesses. The intestine begins in segment xv. The spermathecce are as usual in viii., ix. Each is a thin-walled oval pouch which communicates with the exterior by a much thicker-walled widish duct; into the latter open two sausage-shaped diverticula, one of which appears invariably to lie in front of the other in the segment, in fact in front of that which contains the pouch. The lumen of the diverticula is narrow, and attached to |