THE SIZE OF SPORES 163 



The difference between the average size of the spores for 

 individual fruit-bodies is indicated by the results obtained for 

 Psalliota campestris and Amanitopsis vaginata. The field Mush- 

 room probably belonged to a variety distinct from that of the 

 cultivated ones. It was characterised not only by relatively much 

 longer spores but also by much deeper gills. 



The average diameter of the spores for Specimen III. of 

 Amanitopsis vaginata was 14-3 per cent, larger than the average 

 size for Specimen I. It is clear from this instance that fruit- 

 bodies of the same species may have considerable individual 

 variability in regard to the average size of their spores. 



