. Introduction to structural and systematic botany, and vegetable physiology. Botany. CHOKISIS OK DEDUPLICATION. 245. next within, the lateral and exterior petals; those alternate and within these, the inner circle of petals ; and alternate with these are the anthers of the two stamen-clusters. The centre is occupied by a section of the pistil, which consists of two united. The three sta- mens are lightly connected in Dicentra (Fig. 371) ; but in Corydalis and Adlumia there is only one strap-shaped filament on each side, which is three-forked at the tip, each fork bearing an anther (Fig. 374).
. Introduction to structural and systematic botany, and vegetable physiology. Botany. CHOKISIS OK DEDUPLICATION. 245. next within, the lateral and exterior petals; those alternate and within these, the inner circle of petals ; and alternate with these are the anthers of the two stamen-clusters. The centre is occupied by a section of the pistil, which consists of two united. The three sta- mens are lightly connected in Dicentra (Fig. 371) ; but in Corydalis and Adlumia there is only one strap-shaped filament on each side, which is three-forked at the tip, each fork bearing an anther (Fig. 374). We have a similar case in some Hypericums and in Elodea (Fig. 375), except that, while the floral envelopes are in fives, the circles within tliem are commonly in threes. The three members of the androeciura are normally placed, alter- nating with the three members of the gynascium within, and also with three glands, which probably replace another circle of stamens. Now each real stamen is here multiplied into three, united below; so that the whole compound body may be viewed as homologous with a compound trifoKolate leaf (289). If this be so, then each cluster of numerous stamens in the common St. Johns- wort may be regarded as answering to one stamen greatly multiplied in the same way, and as analogous to a sessile decompound leaf. And the same may be said of each stamen-cluster in the Linden (Fig. 383). The actual development of the cluster, from a protu- berance which in the forming flower-bud occupies the place of a single stamen, has been traced by Duchatre, Payer, &c. in this and other cases. 457. Thus far we are sustained by a clear analogy in the organs of vegetation. As the leaf frequently develops in the form of a lobed, divided, or compound leaf, — that is, as a cluster of partially or completely distinct organs from a common base,—so may the stamen, or even the pistil, become compound as it grows, and give rise to a clus- ter, instead of completing its gro
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