On the relation of assimilation and secretion to the functions of organic life / by J. Gedge.

  • Gedge, Joseph.
Date:
[1869]
Catalogue details

Licence: Public Domain Mark

Credit: On the relation of assimilation and secretion to the functions of organic life / by J. Gedge. 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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    nislied with a nucleus which has definite chemical and physical characters. In this country, as is well known, we are no longer fettered by the vesicular notion of the histological unit: no longer imprisoned by the constant presence of a cell-wall. That the cell should have been universally considered to be vesicular in the early days of histology is not remarkable, when we consider the com- parative ease with which such peculiar cells can be de- monstrated : the imperfection of the optical instruments then in ue not enabling them to study carefully any but the large histological units met with in the vegetable kingdom. Furthermore, it cannot be regarded as surpris- ing that the cell first described should have been con- sidered the type, and that the attempt should have been made to reduce all other cells to the same formula. Besides, in animal cells where no cell-wall esisted, an apparent one could often be made by the action of chemi- cal re-agents. Toy-cells have been constructed by Mr. Rainey and others, having the conventional vesicular character with the indefinite cell-contents simply by mingling certain chemical compounds. The cell-wall then must be understood to be simply a complication of cell structure, which being always absent in the healthy gland-cell and almost all other animal cells, cannot fairly be regarded as a part of the histological unit. But the discussion of this super-added structure, and its histological homology must be reserved until we have entered in greater detail into cell-physiology. The term cell is here used as a technicality for that elementary part or histological unit, which consists of nucleus and plasm ; the nucleus being always distinguish- able by those chemical or physical properties first shown