On the reparative processes which occur in vegetable tissues / by Samuel G. Shattock.

  • Shattock, Samuel George.
Date:
[1881]
Catalogue details

Licence: Public Domain Mark

Credit: On the reparative processes which occur in vegetable tissues / by Samuel G. Shattock. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    together, and resting on a flattened subjacent phellogen; and similar ones are observable in the Hollyhock ; and they may be assumed to be general in plants of the same longevity and like construction. I have seen no proper cicatricial formation of cork in the Bean (Fala vulgaris, Mill.), whether grown under ordinary ex- posure or under the protective conditions of warmth and mois- ture. And it is perhaps true, generally, that the stems of herbaceous plants which last only one season, and in which no provision for leaf-fall exists, are incapable of such reparative process. Indeed, in the Bean, when grown under the usual conditions, I have seen no change whatever in the parenchyma,—at the most a lesser readiness of the cells beneath the surface to react under the iodine and sulphuric-acid test; but even this change is irre- gular and undefined. Frank also notices this absence of repair in the same plant. He speaks, however, of an outgrowth of cells or callus from the cambium. I have observed such an out- growth from the pericambium after amputation of the young root, but have seen no repair of an allied kind after removal of the stem, either in this or any other annual. In Ecbalium, after amputation through the base of the young leaf-stalk, the ends of the fibro-vascular bundles killed in the divi- sion are raised from the deeper parts by the cell-multiplication. The spirals of the vessels may be found unrolled by the parti- tioning increase around, and stretched between the effete and the natural parts. In this way, by lateral compression, attenuation, perhaps rupture, the vessels are permanently closed beneath the temporary crust of sap. Leaving the eflects of amputation in trees for later considera- tion, the case may be next considered of those plants which are intermediate in structure and longevity between herbaceous annuals and exogenous trees. One of the most convenient to take is the common so-called Geranium, Pelargonium sp. If a branch be removed near the parent stem, the cells injured by the division, together with several layers of those beneath, wither, and form a tough buff-coloured membranous layer, beneath which the growth of the living parts uninterruptedly proceeds. The process of growth being maintained in the subjacent parts, the inextensible incrusting substance becomes cracked, and its fragments disparted and loosened from the growing parts beneath,