. Miscellaneous. 299 3. Since I wrote my paper on Mr. Hodgson's collection of fishes, I have ascertained that not only all the Indian species of Therapon enter fresh waters freely, but that several are exclusively freshwater fish. — A. GUNTHER. On the Constitution of the Fruit in the CrucifercB. By M. E. FouRNiER. When a horizontal section is made of a bilocular Cruciferous fruit, especially of a young ovary after the amalgamation of the two parts of the septum, the latter is seen to be bifurcate at each ex-tremity, and to embrace in the angle produced by this bifurcation the elongated column from which the two rows of ovules originate, described by the author as the placenta. This arrangement pro-duces a triangular canal extended longitudinally within each placenta, the horizontal section of which forms a triangle, with its apex at the point of bifurcation of the two lamellae of the septum, and its base upon the placenta itself. The placenta presents, passing inwards, the epidermis, a green parenchyma, cortical fibres, ligneous fibres, and tracheae. The epi-dermis presents projections formed by the cuticle, which are very common in the Cruciferae. The green parenchyma completely sur-rounds the placenta in most genera. It is continuous on each side with the subepidermal parenchyma of the valves, and more internally with the double origin of the septum, which springs directly from it. The cortical fibres exist only on the outer side of the placental column. The woody fibres, which contain chlorophyll at an early period, form around the tracheae a ring which is thicker exteriorly than interiorly. The trophosperms originate from the placenta, sometimes within, sometimes outside of, the triangular canal ; in the former case they perforate one of the lamellae of the septum, to •which they appear to be adnate. The valves present a double epidermis, the outer one with longi-tudinally elongate cells, the interior with transverse cells, arranged in two or three series. Within the outer epidermis there is a paren-chyma, in which vascular bundles ramify in various ways, according to the genera and species ; this is separated from the inner epidermis by a remarkable undescribed fibrous layer. It is formed of very thick fibres, of which the section presents several concentric lines, and strongly refracts light. The form of the section is circular in Lunaria biennis and Fsy chine, elliptical in Sisymbrium. These fibres, when examined in the middle part of the horizontal section, form a simple row in Lunaria and Sisymbrium, several rows with parallel elements in Psy chine, two rows with crossed elements in Fibigia clypeata, Med., and several rows with alternately crossed elements in Itaphanus and Enarthrocarpus. Near the placentas they are always approximated, in several rows, and form a thicker tissue than in the middle of the valve. Analogous fibres are met with in many fruits (Malus, Fraxinus, Nigella, Ervum) ; but they are never so frequent in other families as in the Cruciferae. They are absent from the walls of the ovary in the Resedacex and Capparidacece,
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