Vegetable morphology : its history and present condition / by Maxwell T. Masters.

  • Masters, Maxwell Tylden, 1833-1907.
Date:
1862
Catalogue details

Licence: Public Domain Mark

Credit: Vegetable morphology : its history and present condition / by Maxwell T. Masters. 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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    growth as evinced in the formation of bnds, and the successive produc- tion of node after node, are all cleai’ly explained by Goethe, who on this account also may be considered as the pioneer of that theory of rejuvenescence which Braun has brought to such perfection. There are certain objections which have from time to time been raised against Goethe’s theory, as well as to those of other writers before and after him ■ but it will be moi’e convenient to mention these in conjunction witli the present condition of vegetable morphology than separately. A very simple method of grouping the various modifications met with in the conformation of plants in general, though one not usually adopted, is to classify the several organs or parts of plants into groups, according as they belong to the alimentary, the tegumentary, the re- productive,. the fibro-vascular, and the appendicular systems. A very slight acquaint.ance with plants will suffice to show that many of their organs might as well be included in one as in another of these groups, and in truth might without impropriety be placed in both ; nevertheless the arrangement will be found a convenient one, and probably as little liable to objection as any arrangement of the kind can be in the pre- sent state of our knowledge, or rather ignorance of the relations between structure and functions in plants. The alimentary system contains the organs devoted to the nutrition and growth of plants, including multiplication by “gemmed’’ or buds. The tegumentary or cortical system is sufficiently explained by its title, it corresponds to the exo-skeleton of animals. The reproduc- tive system needs no explanation, the fibro-vascular system corresponds to the endo-skeleton of animals and might be merged with the first group ; the last group, the appendicular, is one inserted here more in deference to generally received opinion than from a conviction of the ] real necessity of establishing such a system as distinct. We shall | endeavour to show as we proceed, how little ground there is for re- I taining such a distinction, and how the organs so classed might more | justly be referred to some of the other groups just mentioned. The groups are arranged according to their relative frequency and importance ; thus, all plants, however simple, have an alimentary ' system j in fact, the simplest concej)tion we can frame of a plant is, as a i gelatinous mass of matter endowed with a mysterious principle, vital I or physical, it matters not wl^ich for our present purpose, manifesting i itself ill the nutritive functions performed by the humble organism. The zoospores of some of the cryptogamic plants are at fii'st mere masses of protoplasm—e.g., Vaucheria, which have a separate existence for a time, an existence too marked by the function of active loco- motion, a function denied to plants higher in the scale. These zoospores speedily become invested by a membrane which completes the “ cell” by forming the cell wall. Indeed, it is doubtful whether a cell wall of membrane, differing in chemical con.stitution, and notably in physical and vital endowments from the primary nitrogenous mass, be not essential to all plants in their adult condition.* The zoospore does not fulfil its ultimate purpose, the formation of a new plant, till it * Cf. Beale's Archives of Medicine, 1801.
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