!8o BOTANICAL GAZETTE [march 



grown mycelia were not suitable for the germination of spores, 

 the spores used in the first cultures were germinated before inocu- 

 lation. This method was extremely unsatisfactory, because the 

 germinating spores could not be evenly distributed in the culture 

 liquid. Moreover, it was found that spores germinated well in all the 

 media used. Attempts to inoculate the flasks by means of the plati- 

 num wire also proved failures, because it was impossible to obtain an 

 even distribution of the dry spores. The method finally adopted, 

 which proved entirely satisfactory, was as follows: A stock-culture 

 on beans, which was well covered with spores, was thoroughly shaken 

 up with the liquid in which it was growing; the liquid was then 

 poured on a screen of fine-meshed muslin in a funnel, and strained 

 into a sterilized flask. This gave a liquid turbid with spores, most of 

 which had been shaken apart and floated free in the liquid. Very 

 little other material passed into the flask. For inoculation three 

 drops of this liquid were dropped into each flask from a sterile pipette. 

 This gave an abundance of spores, perhaps some thousands, which 

 were uniformly distributed in the culture fluid. 



The yield of dry material produced was used as an indicator of the 

 effect of the food given. The yield was determined by adding io cc of 

 a 10 per cent, solution of chemically pure hydrochloric acid to the 

 culture to kill the growth and dissolve any precipitates that had been 

 formed. After this the culture was filtered on a hard filter paper, 

 from which the fungous material was washed into a tared Gooche 

 crucible, and dried at 100-110 C. The variation in the temperature 

 at which the yields were dried was not preventable, since no regu- 

 lated drying oven was available. All the yields of each series were 

 dried at the same time, however, so that they were subjected to the 

 same conditions in drying. The different sets of each series are 

 therefore comparable with each other. 



TABLES AND EXPLANATIONS 



In the following tables are given the results of the cultures, with the 

 necessary explanations relating to each series. In the course of the 

 work many hundreds of cultures were made before finally satisfactory 

 details of manipulation were worked out, and for the purpose of deter- 

 mining the concentrations of the various substances that permitted 



