44 



RESEARCHES ON FUNGI 



gill thus came to be exposed to moist air, without being wetted 

 by free water or receiving mechanical interference from the 

 compressor-cell cover. Usually the hymenium was observed with 

 the low power of the microscope (Zeiss : objective AA, eye-piece 4, 

 tube drawn out full, magnification about 130) ; but, sometimes, 

 when the lid of the compressor cell had been pressed down so that 

 it was in contact with part of the upper surface of the gill, it was 



Average Time taken for the Development and Ripening of an Individual Spore 

 from the Moment the Spore appears on the Sterigma as a Tiny Rudiment 

 until the Moment of Discharge. 



found possible to use the high power (objective DD, eye-piece 4, 

 tube in, magnification about 440). 



The chief difficulty in the application of the method consists 

 in supplying enough yet not too much water to the gill, but 

 experience soon teaches one how to overcome it. Sometimes the 

 gill was laid on the compressor cell without any water being first 

 placed below it. In that case a very little water was touched to 

 the edge of the gill which had once joined on to the flesh. For 

 Hygrophorus ceraceus and Bolbitius flavidus observations showed 

 that it was best not to wet the gills at all. Each case, in the matter 

 of water supply, requires to be considered individually. 



Not infrequently the cover-glass of the compressor cell became 



