SYNTHETIC CHARACTERS OF THE COMMUNITY 77 



The fungus vegetation of the soil also changes in the course of the 

 year and exhibits a species maximum at the beginning of the warm 

 period and a minimum in the winter. Moreover, the soil fungi, mostly 

 saprophytes, seem not to differ appreciably in the different grass 

 associations of the coastal area of eastern England. Elliot (1930), 

 who studied these conditions, found the same soil fungi in the Glycerie- 

 tum maritimae and in the Armerietum ; and even the soil of the Salicor- 

 nietum showed the same soil flora with the exception of two species 

 {Chaetomium spirale and Macrosporium commune). The floristic com- 

 position of the soil fungal vegetation was examined by means of single 

 spore cultures. 



A vibration method has been used by Whittles (1923) for counting 

 soil bacteria. In the vibrator vessel the organisms are freed from the 

 colloids which normally surround them. Thereafter the colonies grow 

 rapidly and in four days reach their maximum, which is much more 

 than would be expected from previous methods. 



On the seasonal variations in bacterial content of the soil and the 

 relation of bacterial development to that of their destroyers, the 

 Protozoa, Cutler, Crump, and Sandon (1922) have given interesting 

 data. 



