CHAPTER III. 
MORPHOLOGY OF MEMBERS. 
Sect. 20. Distinction between Members and Organs ^. Metamorphcsis. 
The parts of plants which are ordinarily termed their Organs — very various in 
their form, and serving different physiological purposes — may be considered scien- 
tifically from two different points of view. The question may be asked at the 
outset, How far are these parts adapted, by their form and structure, to perform 
their physiological work ? In this case they are regarded from one side only, as 
instruments or organs, and this mode of regarding them belongs to physiology. In 
the other case these relationships may be completely put aside, and the question 
may be kept out of consideration what functions the parts of the plant have to fulfil, 
and the only point kept in view may be where and how they arise, that is in what 
manner the origin and growth of one member are related in space and time to 
those of another. This mode of regarding them is the morphological one. It is 
obvious that it is as one-sided as the physiological ; but investigation and description 
require, here as everywhere else in science, abstractions of this kind ; and they are 
not only not hurtful, but even of the greatest assistance to investigation, if the 
investigator is only clearly conscious that they are abstractions. 
In this chapter we shall concern ourselves exclusively with the morphological 
consideration of the parts of a plant. But before we proceed to a more minute 
investigation, it will be useful to get a somewhat more exact comprehension of the 
relationship between the physiological and the morphological view. 
Morphological investigation has led to the result that the infinite variety of the 
parts of plants, which in their mature state are adapted to functions altogether 
different, may nevertheless be referred to a few Original forms ^ if regard is paid 
to their development, their mutual positions, the relative time of their formation, 
and their earliest states ; that, for instance, the thick scales of a bulb, the mem- 
branous appendages of many tubers, the parts of the calyx and corolla, the stamens 
and carpels, many tendrils and spines, &c., altogether resemble, in these respects, 
^ Nägeli und Schwendener, Das Mikroskop. Leipzig 1867, p. 599. — Hofmeister, Allgemeine 
Morphologie der Gewächse. Leipzig 1868, Sect, i, 2. — Hanstein, Botanische Abhandlungen aus 
dem Gebiete der Morphologie u. Physiologie, Bonn 1870, Heft I. p. 85. 
