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Show 1901.] ON AN ANNELID OF THE GENUS ALMA. 215 EXPLANATION OF PLATE XXL Fig. 1. Halonoproctus ricketti (p. 209). Lateral view. 1 a. „ ,, Dorsal view of cephalothorax and abdomen, 1 b. „ „ Ventral view of ditto. 1 c. „ „ Posterior view of abdomen. Id. „ „ Eyes. 2. Latouchia fossoria (p. 211). Sternum. 2 a. „ „ Eyes. 3. „ swinhoei (p. 211). Palp of 3- 3 a. „ „ Anterior view of tarsus and palpal organ. 4. Macrothele palpator (p. 213). Palp of 8- 5. „ holsti (p. 214). Palp of 8. 5. On the Clitellum and Spermatophores of an Annelid Genus Alma. By FRANK E. BEDDARD, M.A., F.R.S. [Eeceived January 31, 1901.] (Text-figures 59 & 60.) Although the genus Alma is now fairly well known owing to the investigations of Levinsen (1), Michaelsen (2, 3, 4), and myself (5, 6, 7), no one has up to the present been able to detect the clitellum. That the spermatophores have not been found is less surprising, since these organs are known in but a small number of extra-European earthworms. I am now able, through the kindness of M r . J. S. Budgett, F.Z.S., to fill in these two lacunae in our knowledge of Alma. This gentleman has kindly placed in m y hands a number of examples of a species of Alma which he collected during his recent expedition to the Gambia. They were gathered on McCarthy Island in that river, and consist of two fully mature specimens and of a few immature worms. The genus itself is purely African, and for the most part " Ethiopian" in range; the only species which reaches the Palaearctic portion of that continent is Levinsen's " Siphonogaster cegyptius,,, which appears to be identical with Grube's (8) Alma nilotica. It is, as I first pointed out, undoubtedly a member of the family Geoscolicidae. It had been formerly regarded, though perhaps with some doubt, as an Eudrilid, to which latter family so many of the Ethiopian earthworms belong. M y observations upon the clitellum confirm the justice of the former view, which is, indeed, definitely accepted by Dr. Michaelsen in his recently issued "Oligochaeten" in the 'Tierreich' (9). H e associates it with the genera Criodrilus and Sparganopliilus in a subfamily Criodrilinae, mainly distinguished from other Geoscolecids by the absence or rudimentary condition of the gizzard. In the generic definition of Alma occurs the sentence " Giirtel fehlt (*?)," an almost necessary query in view of the fact that so many individuals of the genus had been submitted to careful examination, and that in not a single one was there any trace of this characteristic clitellum of the Oligochaeta. It is possibly the case here, as in the aquatic lower Oligochaeta, that the clitellum is only periodically developed, and that it is not so continuous a structure as appears 15* |