The production of leaf-buds from 327 leaves sometimes occurs as in bryophyllum, and many plants of the order Gesneraceae.
When a piece of the stem of bryophyllum is cut off and its leaves are removed, the two apical buds will grow out first.
In some genera of flowering plants, and notably in bryophyllum, little plants form on various parts of the leaves.
In both these respects the shoot of bryophyllum and the flower stalk of Nymphæa give good results.
Eight different determinations are given, three for bryophyllum and five for Nymphæa.