

of removing, measuring and replacing a ^roup of 10 cultures 

 averaged less than 10 minutes* 



The opening of the chambers for the removing and re- 

 placing of the groups of cultures had very little effect upcn 

 the temperature of the chamher itself. The thermographs i 

 the chambers usually showed the occurrence of this series cf 

 momentary openings "by a slight rise cr fall of the pen trac- 

 ing, producing short vertical lines each representing a degree 

 cr less of momentary alteration in the temperature of the cham- 

 ber. 



Several tests were carried out to determine whether 

 the daily disturbance of t^e maintained temperature, caused 

 by removing the cultures for observation mip-ht exert any ap- 

 preciable influence on the growth o^ the fungi. These tests 

 showed that the amount of growth observed after several day3 

 was practically the same whether the cultures had been left 



in the chamber for the whole period or had been removed for 

 dallv observation in the regular way. These dailv disturb- 

 ances of the maintained temperature are considered nep-lipible 

 in the present study. 



THE MAINTAINED TEMPI] .S 



The various temperatures employed in the experiments 

 herein considered were maintained by means of the apparatus 

 described by Livingston and ^awcett^"^ This apparatus con- 

 sisted essentially of seven experiment cham v ers about 33 cm. 

 ir diameter and 43 c?r.. deep, each one surrounded below and 



Vl2^ 



«^^ Livingston, B. E. , and Fawcett, H. L<. , A battery of chambers 



with different automatically maintained temperatures. 



30 



