Sessility (botany) subsessile, which is not completely sessile. Sessility (botany) In botany, sessility (meaning "sitting", used in the sense of "resting on the surface") is a characteristic of plant parts that have no stalk. Flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel. The leaves of most monocotyledons lack petioles. The term sessility is also used in mycology to describe a fungal fruit body that is attached to or seated directly on the surface of the substrate, lacking a supporting stipe or pedicel. Other examples of sessile flowers include Achyranthus, Saffron, etc. Plant
Nutation (botany) 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 is known at present (c. 1915), is dependent upon internal (unknown) causes and is not called forth by the action of external stimuli. The word is often used in a broad sense in the phrase "nutational movement", to include all the movements in plants caused by growth in contrast to "variation