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Nigella Seeds, or Black Cummin. F. A. Flückiger. (Pharm. Journ. Trans., 2nd series, ii., 161.) The seeds of Nigella sativa, a ranunculaceous plant growing on the Mediterranean coasts, in Egypt, Trans-Caucasia, and India, were found by Reinsch, in 1841, to yield 35-8 per cent. of fat oil, 0:8 per cent. of volatile oil, and only 0.6 per cent. of ash. He gave the name of nigellin to a bitter extract, resembling turpentine, yet soluble in water, as well as in alcohol, though not in ether.

By submitting 25 lbs. of fresh seed to distillation, Flückiger has obtained a nearly colourless essential oil, in even smaller quantity than Reinsch. It has a slight odour, somewhat resembling that of parsley oil, with a magnificent bluish fluorescence, as already remarked by Reinsch.

In a column, 50 m. m. long, this oil deviates the ray of polarised light, 9.8° to the left. Its specific gravity is 0-8909. The chief part of it, when distilled with chloride of calcium in a current of dry carbonic acid, comes over at 256o. In an elementary analysis, it yielded-carbon, 83-3, and hydrogen, 11.8 per cent. ; corresponding to the formula, 2 C, H6 H, 0.

The residual portion was almost entirely devoid of rotatory power; it yielded-carbon, 87-89, and hydrogen, 11:72 per cent., after having been rectified by means of sodium. This part of the oil consequently belongs to the terebenes, C H26.

The fat oil extracted by means of boiling ether, from seed grown in Germany, previously finely powdered (necessarily including some essential oil, which imparted to the other its fluorescence), amounted to 25:6 per cent. It is a fluid fat, which does not congeal at 15° ; it was found to consist chiefly of olein; besides which it yielded a considerable amount of a solid fatty acid ; the crystals of which, after reiterated purification, melted at 55°. The melting point did not rise by recrystallisation—the acid being probably a mixture of palmitic and myristic acids.

Nigella seeds, powdered and dried over sulphuric acid, yielded 3:3195 per cent. of nitrogen; answering to about 213 per cent. of albuminous matter.

It is stated in the Pharmacopoeia of India, that nigella seeds are carminative; and they were formerly so regarded in Europe. In the East generally, they are used as a condiment to food; and in Greece, Turkey, and Egypt, they are frequently strewed over the surface of bread and cakes in the same manner as anise or sesame. The fixed oil of the seeds is also expressed for use.

Aconiti Radix. Microscopical Characters. H. Pocklington. (Pharm. Journ., 3rd series, iii. 103.) This root does not.come into commerce in any adulterable form where the use of the microscope is required, but as it is occasionally used in mistake for the roots of Cochlearia Armoracea, it is desirable that the analyst should make himself familiar with its structural peculiarities as compared with those of the latter root. Fortunately the structures of the two roots are as distinct as, or more distinct than, their botanical characteristics. The medulla of Aconitum Napellus is large, angular, and usually well defined by a more or less dark ring. The medullary sheath, or more correctly, for there is no true sheath, vascular en. vironment of the medulla is very incomplete ; and the vascular bundles, which are small and wedge-shaped, are principally situate in the angles of the medulla, and are composed of thin-walled pitted vessels, small in diameter, with oblong transversal pitting, and of wood fibres, un pitted, and of long vessels, apparently transitional laticiferous vessels, containing a dark brown (when the root is dry) colouring matter. The cells of the medulla are large, sinuous in cross section, with moderately thick cellulose walls, and containing great quantities of starch granules. The starch granules are aggregate in three or more, or single, variable in shape with a distinct punctate hilum. A very decided black cross is given by polarised light. The cells of the outer layers differ widely in shape and size. In the immediate neighbourhood of the vascular bundles they form a transitional pleurenchyma with thick-walled cells, only partially attached by their parietes. The more truly parenchymatous cells of this layer are ovate, slightly angular, thick. walled cells, with irregular parietal adhesion, so that numerous

intercellular spaces exist, not only at the angles of the cells, but along the sides and ends, but are very minute in the latter position. The contents of these cells are starch granules imbedded in semialbuminous (?) matter, which becomes deeply stained if a section be immersed in dilute magenta for a short time. Immersion in a weak iodine solution will be found helpful to the elucidation of the more difficult points in the structure of the cell walls and intercel. lular spaces, the more so if the section be transferred from the iodine solution to glycerine jelly, which causes a slight contraction of the then deeply coloured contents, and throws the cell wall into decided prominence. The cuticle layers and the layers contiguous thereto, are much more compressed; those of the cuticle itself possess some interesting features, arising out of their number and the nature of the deposits on the primal membrane of the cell walls. Immediately below the cuticle a few liber cells are found entirely isolate, oval sometimes, extremely elliptical in cross section, and with central cavity. The whole of these characteristics would be discernible in the scraped root if prepared for table in mistake for horse-radish, and most of them could be detected, with a little care, in the partially digested contents of a stomach in the case of a toxicological investigation.

Podophylli Radix. Microscopical Characters. H. Pocklington. (Pharm. Journ., 3rd series, iii., 161.) The structure of the root of Podophyllum peltatum presents several interesting features.

The first thing which will strike the observer on examining a thin cross section is the singular roundness of the large cells of which the major portion of the root is composed. The centre of the root is composed of sub-cylindrical cells, sometimes overlapping each other at their junction by a finger-like extension, which in cross section might be mistaken for a large aggregation of the intercellular substances of Mulder. The adhesion of these cells in linear series is remarkable, and it is easy to separate them into long columns by a short maceration in warm water. They contain great quantities of starch imbedded in a semi-albuminous substance, the deportment of which differs slightly from that of the usual protoplasmic cell contents, with which it is probably intimately allied, but is slightly admixed with dextrinous (?) matter.

A very incomplete vascular ring separates this structure from the cortical series. The vascular wedges are usually .completely isolated, and are small in proportion to the diameter of the root. The vessels are pitted with long narrow pits, and might almost be considered to be scalariform vessels, were it not that they are oval, or

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