Lectures on the physiology of plants . ss more exactly; after the removal of thelaminae there remain only the three motile organs of the leaflets on the commonleaf-stalk, as represented. In A these are very decidedly in the diurnal position:the leaflets are no longer all extended in one plane, but are more upright; at Bthese motile organs have assumed their nocturnal position. It is hardly necessary toadd that as the light varies, and from its after-effects, these organs may assume allpossible positions and curvatures between those of A and B. The coarser anatomical structure is illustrated in
Lectures on the physiology of plants . ss more exactly; after the removal of thelaminae there remain only the three motile organs of the leaflets on the commonleaf-stalk, as represented. In A these are very decidedly in the diurnal position:the leaflets are no longer all extended in one plane, but are more upright; at Bthese motile organs have assumed their nocturnal position. It is hardly necessary toadd that as the light varies, and from its after-effects, these organs may assume allpossible positions and curvatures between those of A and B. The coarser anatomical structure is illustrated in Fig. 368. C is a transversesection through the rigid portion of the leaf-stalk itself; as in most other stiff petioleswhich are channelled above, there are several vascular bundles G arrangedapproximately in a circle, in addition to two more slender ones {g) running in theedges of the channel; the remaining tissues are green cortex c, and soft pith 7«. Theappearance is quite otherwise in the transverse section D of the motile organ,.
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectplantph, bookyear1887
