MORPHOLOGY OF FRUITING STRUCTURES

INFRUCTESCENCES AND FRUITING BEHAVIOR

In Philodendron the developing pistils remain within the reclosed spathe after anthesis and pollination until they are fully ripe (except in the rare case of P. surinamense (Miq. ex Schott) Engl., a South American member of P. subg. Pteromischum which promptly looses its spathe after anthesis). The spathe enlarges somewhat to accommodate the enlarging berries. When the berries are mature the spathe once more begins the process of reopening but the spathe breaks completely free at the base where it is obliquely attached to the peduncle. Sometimes the spathe falls completely free after loosening even before it opens but in general it breaks up beginning at the base and falls off (Fig. 33) eventually falling completely free and leaving a scar just above the peduncle (Fig. 34). Generally the old, withered staminate spadix falls free at this time as well and the berries are exposed on the remaining pistillate spadix (Fig. 33 Philodendron hebetatum). In the process of unfolding, the spathe often develops deep longitudinal fissures which apparently enable it to unfold. Sometimes the old persistent spathe persists on the peduncle with fragments of the inner surface exposed (Figs. 35, 36).