84 THE HISTORY OF CREATION. 



such species as the minute Protococcus, several hundred 

 thousands of which occupy a space no larger than a pin's 

 head. At the highest stage we marvel at the gigantic 

 Macrocysts, which attain a length of from 300 to 400 feet, the 

 longest of all forms in the vegetable kingdom. It is possible 

 that a large portion of the coal has been formed out of Algfe. 

 If not for these reasons, yet the Algse must excite our 

 special attention from the fact that they form the beginning 

 of vegetable hfe, and contain the original forms of all other 

 groups of plants, supposing that our monophyletic hypo- 

 thesis of a common origin for all groups of plants is correct. 

 (Compare p. 83.) 



Most people living inland can form but a very imperfect 

 idea of this exceedingly interesting branch of the vege- 

 table kingdom, because they know only its proportionately 

 small and simple representatives living in fresh water. The 

 slimy green aquatic filaments and flakes of our pools and 

 ditches and springs, the light green slimy coverings of all 

 kinds of wood which have for any length of time been in 

 contact with water, the yellowish green, frothy, and oozy 

 growths of our village ponds, the green filaments resembhng 

 tufts of hair which occur everywhere in fresh water, stag- 

 nant and flowing, are for the most part composed of dif- 

 ferent species of Algse. Only those who have visited 

 the sea-shore, and wondered at the immense masses of 

 cast-up seaweed, and who, from the rocky coast of the 

 Mediterranean, have seen through the clear blue waters the 

 beautifully-formed and highly-coloured vegetation of Algae 

 at the bottom, know how to estimate the importance of the 

 class of Algae. And yet, even these marine Algse-forests 

 of European shoi'es, so rich in forms, give only a faint idea 



