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or grape sugar will call forth the germination of moss spores 

 in complete darkness. Moss protonema are able to attain 

 a considerable size in the dark, by a saprophytic nourishment, 

 although the vigor of growth is considerable below the 

 normal. 



3. Under ordinary conditions of temperature and in- 

 organic nourishment, fern spores are unable to germinate in 

 the dark. A higher temperature will however furnish conditions 

 for the germination in complete darkness. 



4. The spores of Equisetum germinate apparently as 

 well in darkness as in light and at the ordinary room 

 temperature of 19—21° C. 



