CHAPTER 1. 
GENERAL MORPHOLOGY OF THE PLANT, 
THE simplest plants, such as the Red Snow (Protococcus), or 
Gleocapsa, consist of a single membranous sac, or cell as it is 
termed, which in form is more or less spherical or oval. In 
Protococcus (fig. 1) the cells separate almost as soon as formed, 
while in Gleocapsa they remain bound together by an environing 
capsule of gelatinous matter, formed from the cell-wall, for a 
dives 1 Rieu. 
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Fig. 1. Several Red Snow plants (Protococcus (Palmelia) nivalis), magnified. 
Fig. 2. Two plants of Oscillutoria spiralis. 
longer or shorter period. As, however, this matter absorbs 
more water, it is gradually dissolved away and the cells are set 
free. In plants immediately above these in point of complexity 
we find the cells still all alike, but instead of being separated 
and each forming a distinct plant, they are joined end to end and 
form a many-celled filament which is either straight or variously 
curved, as in Oscillatoria (fig. 2). All these plants—so far at 
least as is known—multiply by division of their cells only ; but 
a little higher in the scale we meet with plants in which certain 
of their cells perform the function of nutrition, while others 
are set apart for the purpose of reproduction. Thus, in the 
Moulds, such as Mucor (fig. 3), or Penicillium (fig. 4), the cells 
which serve as organs of nutrition are elongated simple or 
branched filaments, termed hyphx (see page 49), which le 
upon the surface of the substance furnishing the plants with 
food; while those destined to reproduce the individual are de- 
veloped in globular cavities (sporangia), as in Mucor (fig. 3); 
or are arranged in necklace-like branches at the end of special 
filaments, as in Penicillium (fig. 4). 
Yet a little higher in the scale of vegetable life we find the 
cells so combined as to form leaf-like expansions (fig. 5), or solid 
axes (fig. 6), as well as special organs of reproduction (fig. 5, t, t). 
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