THE NUMBER OF SPORES 



85 



dense cloud of spores. These were collected in beakers and then 

 counted. The results given in the Table indicate that the spores 

 were liberated most rapidly during the first twelve hours, and that 

 subsequently the rate of discharge gradually declined. After the 

 first week, spores continued to fall for about three days longer, 

 but they were evidently comparatively few in number and formed 

 but a very thin spore-deposit. Their number was not estimated 

 with the counting apparatus. The total outjDut of spores in the 

 laboratory may be taken as very nearly three-quarters of a billion. 



It may be of interest, for the sake of comparison with the 

 Hymenomycetes, to mention the results of a determination of the 

 number of spores produced by two fungi belonging to other groups 

 of Basidiomycetes. As an average of ten trials with the counting 

 apparatus, the number of spores contained within a single smut- 

 ball of Tilletia caries, developed on Wheat, was found to be 

 12,125,000. The Mushroom mentioned above, therefore, produced 

 as many spores as one hundred smut-balls. But numerous as 

 are the reproductive bodies of a Mushroom, a Coprinus comatus, 

 or a Polyporus squainosus, they pale into insignificance compared 

 with those produced by Lycoperdon bovista, Linn. {L. giganteum, 

 Hussey), the Giant Puff-ball. A large, dry fruit-body of this fungus, 

 collected by Dr. Wright Wilson and given to the University of 

 Birmingham, was found to be 40 cm. long, 28 cm. broad, and 

 20 cm. high. Its weight was 232 grams. The peridium was 

 removed in one place and 0*1 gram of the internal, intact gleba 

 carefully taken out with forceps and weighed. To this small 

 portion of the fruit-body 250 cc. of methylated spirit were added. 



