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July 30 1878 (To illustrate commonness of Heliotropic Action)

Many of the movements affected by the loss of water are beautifully adapted for the needs of plants —Such as the mount of the pollinia of the Orchideae — Some fo them vix Caylex, but the many could be doubted —Again the dispersion of seeds — Or again the allied absorption & drag fo the spiral arm of grasses &c &c — No doubt such movement in [illeg] common [illeg] and [illeg] to plants but perhaps wh came to a certain extent the plants, & were then modified & injured in many ways.—

No one will say that the movement of the pollinia of O. pyramidalis was the chance result of the effect of the drying of caudicles — for stigma peculiar

No doubt in a multitude of plants as to parts dry slightly, there is some curvature & so it may with more for fifty generations, but let the curvature aid the plants in any of its needs & it will be increased — viz if any in any way injurious eliminated, (& it seem probably a curvature in the opposite direction guarded) — Suppose both sides contracted in drying, but one side more than another then by stopping the contraction on one side, curvature on the opposite direction gained —

Over

Hypocotyls pointng to light— so others get less illuminated & therfor decomposet6 less [illeg]

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If very bright light tends to checked growth   or empty cells of water it will on all sides, for some light must go through — if eliminated on near side, then contraction on opposite side —

Hygroscopic movement from drying in pollinia of Orchids like movements of Pulvinus from loss of water.— — only in former case water goes into air

But I imagine that light first causes turges emptying of cells on the most illuminated side &  turgescn of cells on opposite side.