What is "cotyledons"

Usage examples of "cotyledons".

Oxalis corniculata, their development--Sensitiveness of cotyledons to light and consequent disturbance of their periodic movements--Sensitiveness of cotyledons to contact.

Preliminary sketch of the sleep or nyctitropic movements of leaves--Presence of pulvini--The lessening of radiation the final cause of nyctitropic movements--Manner of trying experiments on leaves of Oxalis, Arachis, Cassia, Melilotus, Lotus and Marsilea and on the cotyledons of Mimosa--Concluding remarks on radiation from leaves--Small differences in the conditions make a great difference in the result Description of the nyctitropic position and movements of the cotyledons of various plants--List of species--Concluding remarks--Independence of the nyctitropic movements of the leaves and cotyledons of the same species--Reasons for believing that the movements have been acquired for a special purpose.

But in a future chapter we shall have to recur to the movements of certain cotyledons which sleep at night.

By this latter period the cotyledons had been dragged from beneath the presseddown earth, but the upper part of the hypocotyl still formed nearly a right angle with the lower part.

This hypocotyl became almost straight, and the cotyledons were dragged from beneath the ground on the evening of the second day.

The cotyledons bowed themselves greatly towards the light from 8 to 10.

On a previous day which was uniformly cloudy, a hypocotyl was firmly secured to a little stick, and a filament was fixed to the larger of the two cotyledons, and its movement was traced on a vertical glass.

The hypocotyl of another seedling of the same age was secured to a little stick, and a filament having been fixed to the midrib of one of the cotyledons, the movement of the bead was traced during 14 h.

Therefore the cotyledons certainly circumnutated, though the chief movement was up and down in a vertical plane.

We shall have to recur to the cotyledons of the cabbage in a future chapter, when we treat of their sleepmovements.

We endeavoured to observe the circumnutation of the cotyledons, but as they close together unless kept exposed to a moderately bright light, and as the hypocotyl is extremely heliotropic, the necessary arrangements were too troublesome.

We shall recur to the nocturnal or sleepmovements of the cotyledons in a future chapter.

The cotyledons are in constant movement up and down during the whole day, and as they offer the unusual case of moving downwards late in the evening and in the early part of the night, many observations were made on them.

The position of the two cotyledons was roughly sketched at various hours with the same general result.

In the following summer, the hypocotyl of a fourth seedling was secured to a little stick, and a glass filament with triangles of paper having been fixed to one of the cotyledons, its movements were traced on a vertical glass under a double skylight in the house.