16 



allowing the stock cultures to grow for from ten to fifteen 

 days after which the spore masses were carefully removed 

 with a platinum needle to a clean area on the surface of 

 the agar, from which, after thorough mixing in a little 

 heap, the inoculations to the water cultures were made. 

 This method usually resulted in a satisfactory uniformity 

 in the germination of the spores in the various controls, 

 from which fact it was concluded that all cultures thus 

 made contained an approximately equal number of viable 

 spores, and that any inhibition or modification of germin- 

 ation must have been due to properties of the culture med- 

 ium rather than to differences in the spores introduced. 



In comparing the effect of the various media upon 

 the spores the main criterion was the presence or absence 

 of germination after a period of 18 hours. In many cases, 

 however, germination was more or less modified, as in the 

 production of swollen tubes and other abnormalities, and 

 such modifications of germinal activity needed frequently 

 to be taken into account. As has been indicated, it was 

 seldom necessary to consider the percentage of normal ger- 

 mination which occurred, but in many cases the proportion 

 of abnormal to normal growth was approximately determined. 



The spores of gleosioriura possess several yery 

 favorable features for such an investigation as the pre- 

 sent. Theyare readily wetted by water and aqueous solutions, 

 and, being slightly heavier than water, they sink quickly 

 to the bottom of a hanging drop. They germinate readily in 



