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and hence it might be thought that germination depended 

 upon the elaboration of new material which can only occur 

 to any extent in the less refrangible rays. That this view 

 is highJy improbable is shown by the experiments which 

 follow. 



Cultures of spores were made of the three species above 

 mentioned and placed in C0 2 free air in the light, the appa- 

 ratus being the same as that already used for the moss 

 leaves. The first series of experiments in bright light showed 

 that photosyntax was not necessary for germination, since 

 the spores had germinated as readily in the C0 2 free air as 

 under ordinary conditions. The same result was obtained 

 when the apparatns was exposed to less intense illumination 

 by the interposition of an opaque screen. Under these these 

 conditions the photosyntax would be insignificant and hence 

 it appears evident that germination is independent of that 

 process. The influence of light in germination must be sought 

 then, presumably in a transformation of food products al- 

 ready present in the spore; these chemical changes being 

 initiated by light and only by the less refrangible rays. 

 More in regard to the nature of this transformation will be 

 brought for ward when later experiments are described. 



The question which now presented itself was: Is con- 

 tinued exposure to light necessary for germination, in other 

 words, in there a light induction? In order to determine 

 this point cultures of spores which had been in the dark 

 for twelve hours, were placed in the light and carefully 

 watched for the first signs of germination. After about four- 

 teen hours of illumination the spores showed the first signs 

 of germination, in some cases the extine being burst ; a slight 

 protuberance the beginning of the protonema also being 

 evident. Half of the cultures were allowed to remain in 

 the light as control experiments, while the other half were 

 removed to the dark Chamber to undergo further develop- 

 ment. Those spores which showed no beginning of germi- 

 nation before removed to the dark, did not germinate in the 

 dark although they had formed an abundant Chlorophyll 



