CHAPTER II 



THE RATE OF DEVELOPMENT OF INDIVIDUAL SPORES 

 IN DIFFERENT SPECIES 



Introduction and Table of Results Methods Discussion of Results Effect of 

 Temperature 



Introduction and Table of Results. In order to increase the 

 exact data concerning the production and liberation of spores in 

 the Hymenomycetes, it seemed to me advisable to measure the 

 interval of time which elapses between the first appearance of a 

 spore on the end of the sterigma as a tiny rudiment and the moment 

 of spore-discharge. The first observations of this nature were 

 made upon Calocera cornea and have already been recorded in the 

 previous Chapter. Subsequently, the investigation was extended 

 to a number of other species with spores differing from one another 

 in size, shape, colour, and thickness of cell-wall. The results 

 obtained have been embodied in the adjoining Table. The time 

 given in the fourth column is the average time taken for the de- 

 velopment and discharge of the first of the four spores to be shot 

 away from each basidium. The number of basidia upon which 

 observations were made was usually from three to six. 



Methods. The method generally employed for observing spore- 

 development in the Agaricineae was as follows. A tiny drop of 

 water was placed on the middle of the base of a compressor cell 

 (Fig. 14) and spread out. The whole of a small gill or a large 

 fraction of a large gill was then dissected from a freshly-gathered 

 vigorously-growing fruit-body and laid over the drop, so that the 

 water partly or wholly filled the space between the gill and the 

 glass. Then another small drop was placed on another part of the 

 compressor-cell base. Finally, the cell was closed by its glass 

 cover which was pressed down a little way. The upper side of the 



43 



