Chapter 2

SEEDLING PLANTS. Generality of the circumnutating movement—Radicles, their circumnutation of service—Manner in which they penetrate the ground—Manner in which hypocotyls and other organs break through the ground by being arched—Singular manner of germination in Megarrhiza, etc.—Abortion of cotyledons—Circumnutation of hypocotyls and epicotyls whilst still buried and arched—Their power of straightening themselves—Bursting of the seed-coats—Inherited effect of the arching process in hypogean hypocotyls—Circumnutation of hypocotyls and epicotyls when erect—Circumnutation of cotyledons—Pulvini or joints of cotyledons, duration of their activity, rudimentary in Oxalis corniculata, their development—Sensitiveness of cotyledons to light and consequent disturbance of their periodic movements—Sensitiveness of cotyledons to contact.