54 



RESEARCHES ON FUNGI 



that the extraordinarily long period for spore-development in 

 this species is to some extent due to the very large size of the 

 spores. 



The time taken for the development of a single spore may be 

 divided into two parts : (1) the time employed by the spore in 

 growing to full size, and (2) the time employed in the subsequent 

 process of ripening, which is terminated by spore-discharge. These 

 times are given for a few species in the following Table. 



The Development of Individual Spores. 



From the above data one may conclude that spores usually 

 take longer to ripen than they do to grow to full size from a tiny 

 rudiment ; but to this rule Nolanea pascua, which has curious 

 polyhedral spores, is an exception. We may further conclude that 

 the length of time taken to grow to full size is no indication of the 

 length of time required for the ripening processes. This is shown 

 by the fact that the spores of Collybia fusipes, Collybia dryophila, 

 and Armillaria mellea all take 20 minutes to grow to full size, yet 



