discernible between the barren and fertile flowers of any genus in this Order; witness Tamus, t. 91, though something to the contrary is mentioned in the Genera Plantarum of Linnæus.
7. Polyandria. Under this Order I would certainly comprehend all dioecious plants that have from 8 to any greater number of stamens, according to the example set by Linnæus himself in the last Class. The genera are exceedingly variable in this respect; and if all those the accessory parts of whose flowers are uniform were taken away, the remainder would be so few, that it is hard to say whether any would remain at all. Instances of the Order as it now stands are Populus, t. 1618, 1619; Hydrocharis, t. 808; Mercurialis, t. 559. The fertile flowers of the latter have, in some cases, a nectary or corolla of two slender leaves, not found in the barren ones, which may entitle it to a permanent place here, Carica will also probably remain. Rhodiola can scarcely be kept distinct from Sedum. Coriaria and Ailanthus, having
