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alcohol amount appear assimilation bark become Botanische branches buds calcic cambium carbonic acid cell-wall cellulose cent central cylinder changes chemical chlorophyll chlorophyll granules color containing cork cortex cotyledons crystals cutinized Darwin dicotyledons dilute dissolved ducts elements elongated embryo endodermis epidermal cells epidermis examined experiments fascicles fertilized fibres fibro-vascular bundles flower germination given glass grains growth hairs instance iodine layer leaf leaves light liquid lower plants mass matters micellae microscope minute monocotyledons movement nearly nitrogen nucleus observed oosphere organs outer ovary ovule oxygen parenchyma parenchyma cells petiole Pfeffer pith plants pollen pollen-grains pollen-tube portion produced protein protoplasm radial radicle reagents roots Sachs seedlings seeds shown side soil soluble solution sometimes species specimen stamens starch stem stoma stomata structure substance surface temperature thickness thin threads tion tissue tracheids Transverse trichomes tube vegetable wall wood wood-cells woody yellow young
Page 221 - The colloidal is, in fact, a dynamical state of matter ; the crystalloidal being the statical condition. The colloid possesses energia. It may be looked upon as the probable primary source of the force appearing in the phenomena of vitality. To the gradual mauner in which colloidal changes take place (for they always demand time as an element), may the characteristic protraction of chemicoorganic changes also be referred.
Page 409 - It is hardly an exaggeration to say that the tip of the radicle thus endowed, and having the power of directing the movements of the adjoining parts, acts like the brain of one of the lower animals, the brain being seated within the anterior end of the body, receiving impressions from the sense-organs, and directing the several movements.
Page 416 - But the most striking resemblance is the localisation of their sensitiveness, and the transmission of an influence from the excited part to another which consequently moves. Yet plants do not of course possess nerves or a central nervous system; and we may infer that with animals such structures serve only for the more perfect transmission of impressions, and for the more complete intercommunication of the several parts.
Page 416 - Finally, it is impossible not to be struck with the resemblance between the foregoing movements of plants and many of the actions performed unconsciously by the lower animals. With plants an astonishingly small stimulus suffices ; and even with allied plants one may be highly sensitive to the slightest continued pressure, and another highly sensitive to a slight momentary touch.
Page 297 - ... as an essential property of the gaseous condition of matter. According to the physical hypothesis now generally received, a gas is represented as consisting of solid and perfectly elastic spherical particles or atoms, which move in all directions, and are animated with different degrees of velocity in different gases.
Page 389 - ... case. . . . The growing part, therefore, does not act like a nail when hammered into a board, but more like a wedge of wood, which, whilst slowly driven into a crevice, continually expands at the same time by the absorption of water ; and a wedge thus acting will split even a mass of rock.
Page 222 - But, on the other hand, their peculiar physical aggregation with the chemical indifference referred to, appears to be required in substances that can intervene in the organic processes of life. The plastic elements of the animal body are found in this class.
Page 408 - If the tip be lightly pressed or burnt or cut, it transmits an influence to the upper adjoining part, causing it to bend away from the affected side ; and, what is more surprising, the tip can distinguish between a slightly harder and softer object, by which it is simultaneously pressed on opposite sides.
Page 408 - We believe that there is no structure in plants more wonderful, as far as its functions are concerned, than the tip of the radicle. If the tip be lightly pressed or burnt or cut, it transmits an influence to the upper adjoining part, causing it to bend away from the affected side...
Page 340 - that Pinguicula vulgaris, with its small roots, is not only supported to a large extent by the extraordinary number of insects which it habitually captures, but likewise draws some nourishment from the pollen, leaves, and seeds of other plants, which often adhere to its leaves. It is therefore partly a vegetable as well as an animal feeder.