What is "heliotropic"

Usage examples of "heliotropic".

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.

Our observations were not very successful, as the seedlings are strongly heliotropic, and their circumnutation could not be accurately observed near a northeast window, although they had been kept during the previous day in the same position.

Nevertheless, plants which have ceased through longcontinued darkness to move periodically, if reexposed to the light are still, according to Sachs, heliotropic.

Any kind of movement in relation to light will obviously be much facilitated by each part circumnutating or bending successively in all directions, so that an already existing movement has only to be increased in some one direction, and to be lessened or stopped in the other directions, in order that it should become heliotropic, apheliotropic, etc.

Brassica oleracea, movement of buried and arched hypocotyl, 13, 14, 15 --, conjoint circumnutation of hypocotyl and cotyledons, 16, 17, 18 --, of hypocotyl in darkness, 19 --, of a cotyledon with hypocotyl secured to a stick, 19, 20 --, rate of movement, 20 --, ellipses described by hypocotyls when erect, 105 --, movements of cotyledons, 115 --, -- of stem, 202 --, -- of leaves at night, 229, 230 --, sleep of cotyledons, 301 --, circumnutation of hypocotyl of seedling plant, 425 --, heliotropic movement and circumnutation of hypocotyls, 426 --, effect of lateral light on hypocotyls, 479482 --, apogeotropic movement of hypocotyls, 500, 501 Brassica rapa, movements of leaves, 230 Brongniart, A.

In this position they could not be acted on by apogeotropism, and if they possessed any tendency to straighten themselves or to bend in opposition to their former heliotropic curvature, this would be exhibited, for it would be opposed at first very slightly by apogeotropism.

Phalaris Canariensis: heliotropic movement and circumnutation of a rather old cotyledon, towards a dull lateral light, traced on a horizontal glass from 8.

We have therefore many kinds of gradations from a movement towards the light, which must be considered as one of circumnutation very slightly modified and still consisting of ellipses or circles,--though a movement more or less strongly zigzag, with loops or ellipses occasionally formed,--to a nearly straight, or even quite straight, heliotropic course.

All three floors of the new habitat would open onto the tall concourse, and have terraced broad balconies on the sunny side of the rooms, so that even though the whole structure faced north and was buried deeper than Underhill, the heliotropic filtered mirrors on the other side of the trench would pour light onto them from dawn to dusk.