Nutation (botany) flowers to open or close by movements which resemble the simple nutation of dorsiventral organs. Thus, the tulip, crocus, and other vernal flowers are very sensitive to changes in temperature. The crocus can perceive a change of 0.5°C (0.9°F), and will respond to a change of 20°C (36°F) in two minutes. Nutation (botany) Nutation is the bending movements executed by some plant organs, such as stems, leaves, roots, etc., by which the part is inclined successively in various directions. Nutations are due to the unequal rate of growth of different sides of the organ, an inequality which, so far as
Letters on the Elements of Botany directed at readers with a plant in their hand. Letters on the Elements of Botany Letters on the Elements of Botany () is a work comprising a series of letters written by Jean-Jacques Rousseau on the subject of botany. They were addressed to Mme Delessert in Lyon with the objective of helping her daughters learn botany. They were subsequently translated into English by Thomas Martyn, a professor of botany at Cambridge University, who added notes and corrections to the text. Martyn's translation was originally published in 1785. The letters elucidate the structure of plants and give their order in the