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But from observing the effects of placing plants in the dark, in which case several shoots became in two or three days upright or nearly upright, and when brought back into the light again became rectangularly curved, we believe that the bending is in part due to apheliotropism, apparently somewhat opposed by apogeotropism.

Apheliotropism, or, as usually designated, negative * 'Physiologie Veg.'

Many organs bend downwards through epinasty or apheliotropism or from their own weight; but we have met with very few cases of a downward movement in sub-aërial organs due to geotropism.

Whether the sinking was due to epinastic growth, or apheliotropism, we do not know.

These internodes were either not old enough, or the light was not sufficiently bright, to induce apheliotropism, for both plants bent slowly towards, instead of from the window during four days.