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Show 188 MR. G. F. HAMPSON ON STRIDTJLATION [Mar. 1, or individuals possessed of more than one pair of ovaries we have indications of a metameric reduplication of those organs similar to that of the testes in the Hirudinea. A metamerically repetitional disposition of the ovaries is very rare among worms generally; in fact, it is only met with in the Platyhel-minthes, the Cestoda and the Nemerteans both exhibiting it. Setting aside the Cestoda as highly specialized, we find that the only worms exhibiting the metameric reduplication of the ovaries are certain of the Planarians. Beddard has shown in Eudrilus l that the condition of the oviducts and their accessory structures, to quote bis words, " suggests a comparison with the corresponding organs in the Planarians, from which group I a m disposed (following Lang) to derive the Annelids." The facts which I have herein described and tabulated appear to m e to justify a belief in the potentially reproductive nature of the individual somites of the Chsetopod body, and to support Beddard's suggestion above alluded to. EXPLANATION OP PLATE XIII. Fig. 1. Abnormal Earthworm (Allolobophora, sp. inc.), dissected to show tbe genitalia, X 3. The segmental organs and two posterior seminal vesicles removed from the right side. 1-18, the somites ; sy.o, the segmental organs; m, the mesenteries; n.c, the nerve commissures; s.v, the seminal vesicles; sp, the spermatheca; ; t, the testes ; /, seminal funnels; v.d, the vas deferens ; ov.1-ov.7, the ovaries; ovd, the oviducts; r.o, the receptacula ovorum. 2. Enlarged drawings of the ovaries from the right side, X 10; drawn with a camera lucida. o., nearly ripe ova ; ov.1-ov.'!, the seven ovaries. 3. On Stridulation in certain Lepidoptera, aud on the Distortion of the Hind Wings in the Males of certain Ommatophorince. By G. F. HAMPSON, B.A. Oxon. &c. [Received February 1, 1892.] When working at the Indian Moths of the family Agarislidce, m y attention was drawn by Mr. E. Y. Watson, of the Madras Staff Corps, to the powers of stridulation possessed by the males of yEgocera tripartita, Kirby, of which he had brought home a long series from Burma. This Moth flies at dusk, and the males produce a loud clicking sound audible at some distance off-click-click-click at intervals of about a second. This led m e to investigate the subject in this species and in the only other Lepidoptera known to produce the same sound-certain Butterflies of the genus Ageronia and other allied genera from Brazil. The males of M. tripartita (fig. 1, p. 189) obviously differ from those of all the other species of the genus in the possession of a large patch of hyaline membrane denuded of scales beneath the costa of the fore wing, and this at once suggests itself as being connected 1 " The Anatomy of Earthworms," Q. J. M . S. n. s. vol. xxx. p. 455. |