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In these analyses of tea-ash it will be observed that soda is present in uniformly low quantities. The percentage of iron is lower than that given in some published analyses of tea-ash, but no account is given therein of the alumina which appears to be a constant constituent of the ash, and which was probably included with the iron. The presence of sulphuric acid appears to have been disregarded by most chemists. We find that it is present in remarkably constant percentages.

The sample of "Moning" gives a high proportion of total ash (829), arising from sand and silica. It will be seen on page 28 that a second sample shows only 6.88 per cent.

MICROSCOPIC STRUCTURE.

The leaves of the tea plant vary in size, but seldom exceed

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2 inches in length and 1 inch in breadth (Fig. 1, A and B).

The form of the leaf is that of an ellipse, terminating in a slightly emarginate apex. The margin is dentate, each tooth supporting a

FIG. 2.-TEA.

short caducous spine.

The spines are best seen on the fresh

green leaf, of which an enlarged representation is shown in Fig. 2.

The principal veins proceed from different points of the midrib, ending in curvatures within the margin, and forming on each side of the midrib a row of oblong meshes or loops.

The epidermis of the under surface of the leaf, seen under the

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microscope, consists of well-marked sinuous cells with numerous oval stomates, and a few simple unicellular tortuous hairs (Fig. 3). The skin of the upper surface is similar in structure, but the cells are smaller, and there are no stomates.

The interior of the leaf is made up of fibro-vascular tissue, like that composing the midrib and veins, surrounded

on all sides by a network of round or oval cells filled with chlorophyll grains (Fig. 4, A). Scattered amongst these cells are peculiar branched bodies which have been sometimes called "branched and spinous hairs" (Fig. 4, c), but which are, in reality, branched, thick-walled cells. There are also

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present in the leaf numerous sphæraphides and other plant crystals.

Chief Characteristics.-These are the looped or meshed venation of the leaf, the dentate margin with the short spines, the slightly emarginate apex, the numerous stomates, the unicellular hairs, and the peculiar branched cells referred to.

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