possible conditions as determining the cl-served growth rate 

 in any case ; the growth rate is thus regarded as a function 

 of six independent conditions ; initial internal conditions 

 (a)» initial conditions of the medium (its physical and chemi- 

 cal properties (m), initial radiation conditions (d), the 

 length of the observation period (p) and the location of this 

 observation period, or time interval, serially from the moment 

 of inoculation (n) . 



It may therefore he said that the growth rate (G) is 

 a function of these six conditions a, m, t , d, p ,& n, = f 

 ( d, m, a, t, p, n). The four fungi present four different 

 values of a. Only one value of m was encountered^**; and 



only one value of d was tested (almost complete absence of 

 radiation) . A number of values of t. (maintained temperature) 

 vrere tested. A number of values of p_ were considered, one, 

 two, three, four, five and six days. Five different values 

 of n (the first to the fifth 24 hour period inclusive) were 

 considered. Since two of the conditions (d_, m) were studied 

 by means of only a single value of each, these two were always 



constant and we may say - that the growth for the medium used 

 (m), and for the culture without radiation (d), with a time 

 period of 24 hours (p), is a function of the kind and con- 

 dition of the fungus used (a) the maintained temperature 

 (t), and the location (n) of the time interval considered 

 in relation to the moment of inoculation. 



If G' denotes the growth rate with the given med; . 

 with radiation excluded, we may write G, 1 = f (a, t, p, n) , 



it being understood ir this and the following statements that 



^ Changes in the medium du^inpr the growth of a. fundus will be 

 considered later for m is the initial condition of the medr^ 



