Page:Miscellaneousbot01brow.djvu/530

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512 ox THE OllGANS AND MODE OF FECUNDATION

and altliouo-li it seems to be on the surface is in realitv covered by the outer Lamina of the cell. There is no regu- larity as to its place in the cell; it is not unfrequently however central or nearly so.

As only one areola belongs to each cell, and as in many cases where it exists in the common cells of the epidermis it is also visible in the cutaneous glands or stomata, and in these is always double, — one being on each side of the limb, — it is highly probable that the cutaneous gland is in all cases composed of two cells of peculiar form, the line of union being the longitudinal axis of the disk or pore.

This areola, or nucleus of the cell as perhaps it might be termed, is not confined to the epidermis, being also found not only in the pubescence of the surface, particularly when 711] jointed, as in Cypripedium, but in many cases in the parenchyma or internal cells of the tissue, especially when these are free from the deposition of granular matter.

In the compressed cells of the epidermis the nucleus is in a corresponding degree flattened ; but in the internal tissue it is often nearly spherical, more or less firmly ad- hering to one of the walls, and projecting into the cavity of the cell. In this state it may not unfrequently be found in the substance of the column, and in that of the perian- thium.

The nucleus is manifest also in the tissue of the stigma, where, in accordance with the compression of the utriculi, it has an intermediate form, being neither so much flattened as in the epidermis, nor so convex as it is in the internal tissue of the column.

I may here remark, that I am acquainted with one case of apparent exception to the nucleus being solitary in each utricidus or cell, namely in Bletia Tanker villicB.

In the utricuU of the stigma of this plant I have gene- rally, though not always, found a second areola apparently on the surface, and composed of much larger granules than the ordinary nucleus, which is formed of very minute granular matter, and seems to be deep seated.

Mr. Bauer has represented the tissue of the stigma in this species of Bletia, both before and as he believes after

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