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The salivary glands, opening by a short common duct into the under side of the mouth, in the same general position as in insects, are evidently, as the embryology of the animal proves, transformed nephridia, and being of the arthropodan type explain the origin and morphology of those of insects. It is so with the slime glands; these, with the coxal glands, being transformed and very large dermal glands. Those of insects arose in the same manner, and are evidently their homologues, while those of Peripatus were probably originally derived from the setiparous glands in the appendages (parapodia) of annelid worms.

Fig. 4.—A, Peripatus novæ zealandiæ.—After Sedgwick, from Lang. B, Peripatus capensis, side view, enlarged about twice the natural size.—After Moseley, from Balfour. C, Anatomy of Peripatus capensis. The enteric canal behind the pharynx has been removed. g, brain; a, antenna; op, oral or slime papillæ; sd, slime gland; sr, slime reservoir, which at the same time acts as a duct to the gland; so4, so5, so6, so9, nephridia of the 4th, 5th, 6th, and 9th pairs of limbs; cd, elongated coxal gland of the last pair of feet; go, genital aperture; an, anus; ph, pharynx; n, longitudinal trunk of the nervous system.—After Balfour, from Lang. D, Portion of the body of Peripatus capensis opened to show the scattered tufts of tracheæ (tr); v, v, ventral nerve cords.—After Moseley.