274 OBSERVATIONS ON PLANTS
the term aperta. It is constantly conjoined, and, perhaps, necessarily connected, with the early opening of the calyx, whose segments are originally connivent and slightly imbri- cate : for it may be here remarked, that in all the modifi- cations of what I have termed imbricate aestivation of petals, they are, I believe, in the very early stage in like manner erect, and the sexual organs equally exposed.
If the expediency of preserving the genus Cleome entire were admitted, a question which I do not pretend at present to decide, it w^ould still be of the greatest importance to arrange its numerous species according to their affinities, and carefully to distinguish the subordinate groups that compose it. To such inferior groups, whether termed subgenera or sections, names, in fact, have been of late years very generally assigned, both by zoologists and botanists.
It has not yet been proposed, however, that these sub- generic names should form an essential part of the name of the species ; although by employing them in this manner, w^hile the principal groups would be kept in view, their subdivision vvould be carried to the same extent^ and the subordinate groups as well expressed, as if they had been actually separated into distinct genera.
The adoption of this method, which would not ma- terially distiu'b names already existing, would probably lead to a greater consistency in the formation of genera, with reference to the natural orders of which they are sub- divisions. In this way also the co-operation of two classes of naturalists, at present opposed to each other on the question of the construction of genera, might to a certain extent be expected, and greater uniformity in nomenclature consequently secured.
These advantages appear to me so important, that some expedient for obtaining them will, I am persuaded, at no distant period, be generally adopted.
In favour of the present plan it may be remarked, that it is analogous to the method followed Ijy the Romans in the construction of the names of persons, by which not only the original family, but the particular branch of that family to
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