Les plantes insectívores
- Idioma:
- anglès
- Completesa:
- Obra completa
- Autoria:
- Escrita per l'autor
- Estat del text:
- Sense soroll d'escaneig detectat (mesura automàtica sobre tot el text, no revisada a mà)
- Extensió:
- ~170.000 paraules · 792 passatges
Cita aquesta obra
- APACharles Darwin. (n.d.). Insectivorous Plants [Les plantes insectívores]. Digital reproduction: SigPhi. https://sigphiai.com/ca/works/charles-darwin/insectivorous-plants
- MLACharles Darwin. Insectivorous Plants [Les plantes insectívores]. Digital reproduction, SigPhi, https://sigphiai.com/ca/works/charles-darwin/insectivorous-plants.
- ChicagoCharles Darwin. Insectivorous Plants [Les plantes insectívores]. Digital reproduction, SigPhi. https://sigphiai.com/ca/works/charles-darwin/insectivorous-plants.
Referència de l’edició reproduïda. SigPhi és la reproducció digital, no l’editor. S’hi inclouen l’any, l’editorial i el traductor quan consten; «n.d.» indica que no consta l’any. La responsabilitat d’un pròleg o d’una nota es determina segons el passatge citat.
De què tracta
El llibre del 1875 en què Darwin va documentar, experiment rere experiment, que hi ha plantes que capturen animals, els digereixen i n'aprofiten el nitrogen.
Context i història
Ho va fer amb els mitjans de casa: gotes de saliva, trossos de carn, vidre, cabells, sals, tot pesat en quantitats minimes, per veure a que reaccionava la drosera i a que no. La descoberta que va sorprendre mes els seus contemporanis es que la planta distingeix: respon a la materia nitrogenada i no a un pes inert equivalent. El llibre importa per dues raons alhora. Es una peca de la seva argumentacio general —una planta carnivora es una adaptacio extrema i mostra fins on arriba la seleccio natural—, i es tambe un model de com es fa una investigacio: tot esta anotat, incloses les proves que no van donar res. Darwin va publicar mes llibres de botanica que sobre l'evolucio, i aquest es dels millors.
Context editorial, no una font citable: a diferència dels passatges de l'obra, aquestes dades no es poden contrastar amb el corpus.
for the communication of a motor impulse to other parts of the leaf, as we may infer from the structure of the glands in some other genera of the Droseraceae. The extreme marginal tentacles differ slightly from the others. Their bases are broader, and besides their own vessels, they receive a fine branch from those which enter the tentacles on each side. Their glands are much elongated, and lie embedded on the upper surface of the pedicel, instead of standing at the apex. In other respects they do not differ essentially from the oval ones, and in one specimen I found every possible transition between the two states. In another specimen there were no long-headed glands. These marginal tentacles lose their irritability earlier than the others; and when a stimulus is applied to the centre of the leaf, they are excited into action after the others. When cut-off leaves are immersed in water, they alone often become inflected. The purple fluid or granular matter which fills the cells of the glands differs to a certain extent from that within the cells of the pedicels. For when a leaf is placed in hot water or in certain acids, the glands become quite white and opaque, whereas the cells of the pedicels are rendered of a bright red, with the exception of those close beneath the glands. These latter cells lose their pale red tint; and the green matter which they, as well as the basal cells, contain, becomes of a brighter green. The petioles bear many multicellular hairs, some of which near the blade are surmounted, according to Nitschke, by a few rounded cells, which appear to be rudimentary glands. Both surfaces of the leaf, the pedicels of the tentacles, especially the lower sides of the outer ones, and the petioles, are studded with minute papillae (hairs or trichomes), having a conical basis, and bearing on their summits two, and occasionally three or even four, rounded cells, containing much protoplasm.…