Page:Natural History Review (1862).djvu/33

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ORGINAL ARTICLES.

the exterior envelope appear first and the central swelling later, the body is a pistil, because the carpel always appears earlier than the ovule.

This mode of discovering the nature of the parts fails only in cases where a single ovule appears to be a direct continuation of the axis, as in Rheum,Polygonum, &c. because in these cases it is impossible to decide upon the instant of time at which the apex of the axis becomes changed into the nascent ovule or its nucleus, Baillon,indeed, mentions that the ovules of Conifers arise from the axis; but if the contrary view be established, the test of priority of origin may certainly be applied to the determination of the nature of the different parts of the organ under consideration.

Early in January, 1861, I examined, for the purpose of testing M. Baillon's statement, the female flowers of Thuja orientalis L., Taxus baccata L., Cupressus sempervirens L., Callitris montana, Juniperus communis L., J. sphærica Lindl., J. Sabina L., J. virginiana L., and Pinus Larix L. The climate of Regensburg not being hot enough to enable Gingko biloba, Phyllocladus or Torreya to flower, even in the greenhouse, I regret not to have had it in my power to examine more than a very few of the species on which M. Baillon's observations were made.

With the exception of the Larch, the flowers of all the plants which I examined were almost fully, or at least half, developed; but even in this state of advancement I was led to doubt the accuracy of M. Baillon's statement, that the outer covering (or integument of authors) consists of two carpels. For when two carpels are present, two separate apices (styles, Baillon calls them,) may be expected to be visible; and, in fact, all Baillon's figures of the adult organs in question show two lobes or spices, as in the figure of Pinus resinosa t. i. f. 23, &c., Thuja orientalis, t. ii. f. 17, Cupressus sempervirens,t. ii. f. 20, 21, Phyllocladus rhomhoidalis, t. ii. f. 24, Taxus baccata, t. ii. f. 14, 16. Except, however, in the Yew, in which I found the micropyle to present the appearance of an arched or more rarely straight fissure, the ends of which are opposite to the two highest leaf-scales (bracts), the margin of the organ in question (Baillion's pistillum) was not, in the plants I examined by any means constantly two-lobed, and in the Jumpers I never observed it to be so. The margin of the "pistillum" of Juniperus sphaerica, which appeared fully developed, was invariably entire, and formed by a circle of ten or eleven cells. In the other species of Juniper it was generally obliquely truncate, and in the same species, nay even in the same specimen, it was at one time irregularly sinuate or repand or toothed, at another emarginate on one side or perfectly entire. In Callitris montana the orifice was very wide and surrounded by about twenty cells, and its margin was either irregular or repand, or 3-4-toothed, or quite entire. I never saw it two-lobed. In Thuja orientalis and Cupressus sempervirens, in which Baillon always figures it as two-lobed, I found it occasionally so, but more frequently the orifice was irregularly sinuate or