MONERA 



In the same way, the surface of the Arctic Ocean is often 

 colored brown or reddish-brown by masses of the brown 

 procytclla prhnordialis (formerly described as protococciis 

 niarinus). 



It is clearly quite illogical to regard the chromacea as 

 a class or family of the algae, as is still done in most 

 manuals of botany. The real algae — excluding the 

 unicellular diatomes and paulotomes, which belong to 

 the protophyta — are multicellular plants that form a 

 thallus or bed of a certain form and characteristic tissue. 

 The chromacea, which have not advanced as far as the 

 real nucleated cell, are unnucleated cytodes of a lower 

 and earlier stage of plant-life. If one would compare 

 the chromacea with algae or other plants at all, the 

 comparison cannot be with their constituent cells, but 

 merely with the chromatophora or chromatella, which 

 are found in all green plant-cells, and form part of their 

 contents. To be more precise, these green granules 

 of chlorophyll must be regarded as organella of the 

 plant-cell, or separated plasma-formations which arise 

 beside the nucleus in the cytoplasm. In the embryonic 

 cells of the germs of plants and in their vegetation 

 points the chromatophora are as yet colorless, and are 

 developed, as solid, very refractive, globular, or roundish 

 granules, from the firm layer of plasm which imme- 

 diately surrounds the nucleus. Afterwards they are 

 converted, by a chemical process, into the green chloro- 

 phyll granules or chloroplasts, which have the most 

 important function in the plasmodomism or carbon- 

 assimilation of the plant. 



The fact that the green chlorophyll granules grow 

 independently within the living plant-cell and multiply 

 by segmentation is very important and interesting. The 

 globular chloroplasts are constricted in the middle, and 

 split into two equal daughter-globules. These daughter- 

 plastids grow, and multiply in turn in the same way. 



195 



