106 Miscellaneous. brownish, underlined with reddish brown ; a reddish spot on inner margin near base ; faint traces of a rusty brown inner line and wavy exterior line at five sixths ; a small brown subcostal spot in middle of cell ; two snow-white spots on the angles of the cell, the upper the larger, edged with brown, and lying in a small brown blotch; fringe and nervures towards hind margin faintly tinged with brown. Hind wings with discal spot and sinuous indistinct central line ferruginous j fringe and hind margin much tinged with brown; face yellow, with a narrow reddish bar at base ; shoulders with a reddish line at sides ; collar, patagia, thorax, and abdomen all gilded yellow ', thorax with a red-brown central spot and the crest red-tinted ; second segment of abdomen with two largish reddish spots ; anal tuft reddish brown ; palpi dark brown, the basal joint white. Underside paler yellow, with very faint markings. Expanse of wings 24 millim. One male, Queensland. [To be continued.] MISCELLANEOUS. Contrihutmis to the Emhryogeny of Simple Ascidians. By Anioine Pizon. Several points in the development of the Simple Ascidians are still disputed or unknown, especially the origin of the peribranchial cavity, the relations of the sensory vesicle to the neighbouring parts, and the existence of an epicardium analogous to that which is found in the Compound Ascidians. The species which I have had at my disposal for the purpose of studying these different points are Cynthia morus and Ascidia villosa, Giard. The earliest phenomena of segmentation are dissimilar in these two species, and this is due to the fact that Cynthia moms possesses an enormous quantity of food-yolk, of which we still find a con-siderable portion in the larva at the moment of hatching. I^ After the formation of the cavity of the archenteron in Ascidia villosa, its walls send out two lateral extroflexions which grow pretty rapidly, while each of them speedily attaches itself to the ectoderm. The latter layer on its part becomes slightly invaginated at the two points of contact and then perforated ; the larva hence-forth exhibits two new apertures, which are added to that of the stomoda^um, and the existence of which was first demonstrated by Krohn and Kovalewsky. The enteric cavity is gradually enveloped by the dilatation of its two diverticula, which become the peri-branchial cavity. The two lateral apertures are thrust more and more into the median line on the dorsal side in consequence of the development of the larva ; finally they unite and form but a single orifice, which will be the cloacal aperture of the adult.
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