Miscellaneous. 465 Epithetosoma, g. n. Body cylindrical, furnished at its anterior end with a long, non-retractile, tubular appendage (proboscis). Behind this, on the ven-tral surface, the round buccal aperture. On each side of the anterior extremity of the body a fissure, which is furnished with several apertures at the bottom ; no anal appendages ; anus at the posterior extremity of the body. Epithetosoma norvegicum, sp. n. Body cylindrical, 12 millims. long, 2 millims. broad. The tubular appendage two and a half times as long as the body ; intestine the same, much folded. Colour of the body olive-green, of the pro-boscis pale greenish. One example, taken at Station 190 in G9° 41' N". lat., 15° 50'-5 E. long., at a depth of 870 fathoms, on a bottom of sandy mud. — Nyt Magazin for Naturvid. 1 880, pp. 44-66. On the Existence of Polar Globules in the Ovum of the Crustacea. By M. L. F. Hennegut. Grobben is the only author who has hitherto noticed the pre-sence of polar globules in the ovum of the Crustacea. He states that he saw, in the ovum of Moina rectirostris, a small clear spot situated at the superior pole, enclosed in the vitellus, which he re-gards as a polar globule flattened by the envelope of the ovum which is closely applied to the vitellus. On examining recently laid ova of Asellus aquations I saw, in the tolerably wide space which separates the vitellus from the chorion, two small transparent globules, containing a few granules and presenting all the characters of the polar globules observed in the ova of other animals. I have even been fortunate enough twice to see one of these globules detach itself from the vitellus. In all the ova that I have examined, these little bodies were nearly of the same diameter. In some ova there were four of them, forming a little group ; and they were then smaller than in the ova in which there were only two : it is probable that in this case the two globules had divided. These globules persist for some time in the ovum, and only dis-appear when the vitellus is already divided into about ten segments. The first segmentative grooves forming simultaneously around nuclei which make their appearance at the surface of the vitellus, the polar globules do not here play any part in relation to the pro-duction of the first segmentative furrow, and cannot be regarded as directive corpuscles. Their formal ion is very probably connected with the disappearance of the germinal vesicle, as Eol and Hertwig have demonstrated in the case of the Echinoderms ; but the opacity of the vitellus has not allowed me to sec the germinal vesicle, or to witness its disappearance. — Bull. Soc. Philom. Paris, April 10, 1880.
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