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Rh lobed, irregularly crenate, or even quite entire. Richard, too, thus describes the organs of certain Conifers, e.g. Pinus Cedrus, "margin unequally and irregularly cut into 2-5 segments, which are irregularly erose toothed or repand;" and Pinus balsamea, "limb longer on one side and slightly divided at the margin into two or three somewhat unequal lobes." These descriptions and figures throw still more doubt on the existence of Baillon's "two carpels." It was, however, in Pinus Larix, in which I fully studied the evolution of the cone-scales, that I acquired a complete conviction of Baillon's error. In this plant, what Baillon calls the ovule, appears first in the form of a convex, almost hemisphærical boss, around which, some weeks later, the integument is produced, not under the form of two distinct horseshoes, but of a complete ring, uniform in height all round. I tried in vain to find any indication of a double origin. It is impossible to consider the floral organ of Pinus Larix as anything else than a nucleus surrounded by an integument, that is, an ovule; and as it is incredible that the integument of Pinus Larix should, from the first, be a regular ring, while that of the other Conifers examined by M. Baillon presents, in its earliest condition, the appearance of two horse-shoes, the observations of MM. Baillon and Payer appear to me more than doubtful.

Were it however the case, that in some Conifers this integument originated as two distinct tubercles, it would by no means necessarily follow that these two tubercles indicate the presence of two organs of distinct origin, not referable to the integument of the gemmule. For:

1. Two-lipped integuments are occasionally met with, which no one regards as two distinct carpels. Thus in Polygala comosa the outer coat of the ovule is produced obliquely upwards and subcucullate, and is divided by a deep fissure into two lateral lobes. Payer makes no mention of these in Polygala speciosa, though he figures the ovule-coat of Tremandra verticillata as two-lipped, which is only the case at a late stage of the development of the ovule. The period at which the lips appear seems, however, of little consequence.

2. Other organs certainly exist, which, though single and not composed of two united together, do yet, at their first appearance, show two distinct apices, as, for instance, the stipules of Victoria regia and Euryale ferox, whose evolution I have examined, and the upper palea of grasses which Payer himself describes and figures in Briza media, Panicum aduncum, Triticum monococcum, Ehrkarta panicea and Stipa juncea.

3. There are certain ovules whose coats sometimes originate equally all round, while at other times, in the same species and even in the same ovary, they are visible on one side earlier than on the