upper part of the spike; and this relation also exists in the more compound inflorescence of Ricinus, Syphonia, and Celtis, in which the order of expansion is equally inverted.
It may seem rather paradoxical to select Euphorbia as an example of the same relation; this genus being considered by Linneus, and the greater part of the botanists who have adopted his system, as having a dodecandrous hermaphrodite flower. We have already, however, I believee sufficient evidence that this supposed hermaphrodite flower is in reality formed of several monandrous male flowers surrounding a single female[1].
In conformity with this view of its composition, and with the
relation above attempted to be established, the development of
the pistillum precedes that of the stamina in many species of the
genus.
It is more difficult to determine whether this order of expansion and relative position of sexes in Euphorbia be in conformity with the general rule, or an exception to it. For its faciculus of flowers may be considered as analogous either to the simple spike, and. consequently having an inverted order of expansion, as in Allium descendens, and certain species of Grevillea and Anadenia: or it may be assimilated to the compound spike, as in several species of the genus the male flowers appear to be separated into fasciculi;
- ↑ To the arguments I have adduced (in my Remarks on the Botany of New Holland) in support of this opinion, I am now enabled to add the more direct proof derived from certain species of Euphorbia itself, in which the female flower is furnished with a manifest calyx. I have formerly observed, that in a few cases the footstalk of the ovarium is dilated and obscurely lobed at top: but in the species now referred to it terminates in three distinct and equal lobes of considerable length, and which being regularly opposite to the cells of the capsule may be compared to the three outer foliola of the perianthium of Phyllanthus, between which and the cells of the capsule the same relation exists. This calyx is most remarkable in an undescribed species of Euphorbia from the coast of Patagonia, in the Herbarium of Sir Joseph Banks; but it is observable, though less distinct, in E. punicea and several other species.
