Streptocarpus mit Brutblatt

Abstract:

Streptocarpus with a brood leaf

In the genus Streptocarpus (Gesneriaceae) the usual generation of new leaves on the shoot is more or less replaced by a generation of new leaf parts on the bases of abundant leaves. This indicates a homology between shoot growth and leaf growth. ‚Interesting malformations are described which could help better to understand the relationship between the generation of new leaves and the enlargement of leaf blades as well as the process of maturation of the single leaf. These maliormations are associated with a hypertrophy of leaf margin crenatures which hear new plantlets as in Bryophyllmn (Crassulaceae). Because of the special form of further growth, the crenatures in Slreptocarpus show directly their homology with the leaf base. 30 the latter appears as only an enlarged sector of the margin of the leaf among many others like it. The leaf is not only a marginal outgrowth of the shoot, but also bears a centre of plant formation in itself. This finding further verifies Goethe’s idea of plant metamorphosis.