CHAPTER XII 



THE MECHANISM OF SPORE-DISCHARGE 



In the last chapter it was shown that the spores of Hymenomycetes 

 are discharged from the sterigmata in a violent manner. The 

 mechanism by which this process is brought about will now be 

 discussed. 



Brefeld/ in a footnote to his account of the life-history of 

 Coprinus stercorarius, has stated that all the four spores of a 

 basidium are discharged simultaneously, and that, immediately 

 after a discharge, small drops are left upon the vacant sterig- 

 mata and also on the spores. He came to the obvious and 

 apparently sufficient conclusion that the spores are shot forward 

 on account of the bursting of the sterigmata and the ejacu- 

 lation of their contents. However, after studying the discharge 

 of spores in several species of Coprinus, as well as in Polypcn^us 

 squaTiiosus, Psalliota campestris, &c., I find myself unable to 

 confirm Brefeld's observations. The facts brought forward in 

 the last chapter ^ afford conclusive proof that the four spores 

 of a basidium are discharged not simultaneously but successively. 

 By applying my Method IV.^ to the examination of a gill 

 margin (Plate II., Fig. 12) of a ripe Coprinus fruit-body, any one 

 may observe the successive discharge of the four spores from 

 scores of basidia in a few minutes. The shooting off of all four 

 spores usually occupies from about one to several minutes. At the 

 moment of discharge of the spores from the basidia of Coprinus 

 comatus, Folyporus squamosum, &c., I have endeavoured to observe 

 drops on the vacant sterigmata, but without success ; nor, by using 

 .my Method I.,^ have I been able to detect drops on any spores as 



1 Brefeld, loc. cit. ^ Under Method IV. 



" Chap. XI. * Chap. XI. 



148 



