Page:Natural History Review (1861).djvu/105

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PHANEROGAMIA.
93

pellary leaves, horse-shoe shaped, and with their concavities turned towards each other. These become connate, forming round the plane receptacle an elliptical enclosure. With the growth of the axial "scale" the position of the rudimentary flower alters—at first with the aperture directed laterally, it afterwards becomes directed slightly downwards. The carpellary leaves elongate, forming, as it were, an ovarian sac, continuous below, and divided above into two styline branches (branches stylaires). In the centre, at first free from the surrounding carpellary walls, is developed, in direct prolongation of the floral receptacle, a rounded swelling, which eventually forms the basilar ovule.

In Cupressus, the floral axis, which is similar to that of Thuja and Salisburia bears empty bracts. Above each bract, and at a tolerable distance from their insertion, a dicarpellary pistil originates opposite to their median line. Soon another flower is produced in front of, and below, the first, then two others upon the sides; additional flowers develope exterior to these, and lower en the axis, surrounding them in several irregular circles. Thus is formed a small, centrifugal, axillary inflorescence, in some measure comparable to the axillary glomerules of the Labiatæ, which, as in Cupressus, collectively form a kind of spike.

Dr. B. embodies the results of his investigation in the following propositions:—

1. The female flowers of the Coniferæ differ but slightly from each other in essential particulars. They are formed upon one type, and, regarded apart, afford no basis for the division of the Order into Pinaceæ and Taxaceæ.

2. The female flower is either terminal, or borne in the axil of a bract or of a leaf. It is always, however, as Schleiden also remarks, supported upon an axial process, and never upon a bract. As is the case in receptacles, the form of this axis is very variable.

3. As also Mirbel and Spach have regarded it, the flower is not gymnospermous, but possesses a true dicarpellary ovary, without floral envelopes, containing an orthotropal, erect ovule attached to a basilar placenta.

4. The cupule of various consistence and form which surrounds the ovary, and which in several genera has received the name of aril, is a later production, although anterior to fecundation, as is the case of those floral organs resulting from an ulterior expansion of the axis, which have been termed discs.

The Memoir is accompanied by figures, exhibiting the consecutive stages of development of the "scales" and female flowers in Pinus resinosa.

Baiträgez.—Pflanzenkunde d. Russischen Reichs.—Part II., plate. Petorsb., 1860, Royal 8vo.

Bentham, George.—Synopsis of Dalbergieæ, a tribe of Leguminosæ.—"Journ. Proc. Linn. Soc.," vol. iv. (Botany, Suppl.), 134 pp. Mr. Bentham, while engaged in editing the Leguminosæ for the "Flora