Fungous Flora of the Soil 



429 





were vigorously shaken at intervals during two to four hours in 

 order to break up the soil lumps and liberate any enclosed fungus 

 spores. 



Toward the end of the summer of 191 1, another method for the isolation 

 of fungi, which can be used apparently to considerable advantage, was 

 perfected. The writer had opportunity to take but one sample to test 

 this method; in this case, however, it yielded very satisfactory results. 

 The method is as follows: A lamp chimney of sufficiently small size to 

 allow the passage of the top through the mouth of a pint or quart fruit 

 jar, when the chimney is inverted, was used as a 

 retainer of the sample. To serve as a support for the 

 soil, four thicknesses of cheesecloth were fastened over 

 the top of the chimney. The base of the chimney 

 was plugged with absorbent cotton. After inversion, 

 the top of the chimney was passed through the mouth 

 of the jar and the chimney placed in position. Absorbent 

 cotton was wrapped about the mouth of the jar and the 

 chimney (Fig. 100). The apparatus was now sterilized. 

 As already stated, fractional sterilization in a modified ^ 

 Arnold was resorted to. 



After sterilization the jars were taken into the field 

 and the soil was introduced into the chimneys after the 

 removal of the cotton plugs. When the samples had 

 been thus disposed of, the plugs were again inserted 

 and the apparatus containing the soil removed to the 

 laboratory. 



On arriving at the laboratory, the soil in the 

 chimneys was moistened with sterile water, care being 

 taken to use only sufficient water to initiate percolation. 

 The apparatus was now set aside until various fungi 

 could be seen in fruiting condition on the cheesecloth. 

 This was readily observed because of the use of the glass jar. The 

 chimneys were now removed and poured plates were made of the 

 fungi in order to obtain pure cultures. A study was made of the fungi 

 in their fruiting condition on the cheesecloth for comparison with those 

 produced in culture. 



Fig. 1 00. — Culture 

 chamber devised for 

 the isolation of soil 

 fungi 



Sterilization oj glassware 



All petri dishes were double-wrapped in manila paper and sterilized 

 for two hours at 140° C. All other glassware, including test tubes, pipettes, 

 bottles, flasks, etc., was sterilized in the hot air sterilizer (except when 

 otherwise stated) for one hour at 140° C. 



