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By the following morning these short bowed portions had straightened themselves through apogeotropism.

The hypocotyls of Beta vulgaris are highly sensitive to apogeotropism.

The sheath-like cotyledons of Phalaris Canariensis are extremely sensitive to apogeotropism.

As soon as any part of the arch protrudes from the seed-coats it is acted upon by apogeotropism, and both the legs bend upwards as quickly as the surrounding earth will permit, until the arch stands vertically.

As soon as the faintest ray of light reaches a seedling, heliotropism will guide it through any crack in the soil, or through an entangled mass of overlying vegetation; for apogeotropism by itself can direct the seedling only blindly upwards.