ON THE PROTEACE.E OF JUSSIEU. 17
but as he has not denned it, and as his commentator lleuss has given the very different aestivation of grasses as an ex- ample, I have, in introducing this circumstance into the general description of the order, specified it at length.
From the colour of the calyx, many genera of Proteaceae are indicated with tolerable certainty. Thus Synapliea is distinguished from Conospermum by its yellow flowers ; and no instance of yellow flowers has been met with in the numerous genera Serruria and Spatal/a, nor any of purple in Leucadendron. In some genera, however, as in Banhia, [29 and Lsopoyon, it is evidently of very little importance.
The fleshy or scale-like bodies, which surround the ovarium in the greater number of plants of this family, are in many cases so manifestly secreting organs, that it is surprising Mr. Salisbury should hesitate in considering them as nectaria, and denominate them calli ; a term w r hich excludes the idea of secretion. But whatever their functions may be, great assistance may certainly be derived from their various modifications, in distinguishing genera. Their importance however in this respect, like that of all other parts, not only in this, but, as I apprehend, in every natural family, is very unequal, and in some cases seems to be entirely lost. Thus, in the genus Leucadendron as it is here constituted, they are wanting in several species, and in some I am inclined to think exist only in the males.
In most of the regular-flowered genera they are four in number, and alternate with the leaves or lacinise of the calyx. In these genera they are also generally in the form of succulent scales, distinct, or more rarely cohering at their base, and in a very few instances adhering to the calyx j but in Persoonia they are nearly round and fleshy, and in Bellendena, Symphionema, Simsia, Ayastachya, Pe- frop/iila, and Lsopoyon, they are entirely wanting.
In the irregular-flowered genera with two or many seeds their number is less than four, in most cases only one exists, in a few others three, and in some none.
Varieties in the structure or apparent origin of the stamina, afford, as might be expected, important generic characters. Their usual insertion in the order is in the
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