Latham : Stimulation of Sterigmatocystis 345 



the economic coefficient fell from 11.493 to 3.214 and 3.201 

 grams per gram fungus respectively. The average figures for the 

 atmospheres quoted are for acid coefficient 0.6932 and 0.5696 and 

 for sugar 3.744 and 3.514 against 1.4123 and 5.358 for the nor- 

 mal culture. The economic coefficient of the controls varies con- 

 siderably from that found by Kunstmann * and Richards,t to be 

 sure, but the figures obtained are fairly stable. The same thing is 

 true of the data for oxalic acid as compared with those of Ono.| 

 That irregular fluctuations may be regarded as due to individual 

 peculiarities is indicated by the consistency in the various factors. 

 For instance, a lack of due increase in weight is, in general, accom- 

 panied by an abnormal rise in the coefficients of acid and sugar, 

 pointing to internal differences rather than to errors in calculation 

 or manipulation. 



Chloroform belongs to the so-called catalytics in Loew's 

 classification. The small amount absorbed by the water of the 

 nutrient solution affects the protoplasm so as to cause it to work 

 more economically, possibly through action on the enzyme 

 formed. 11 However that maybe, the figures point again to the 

 explanation of the phenomena advanced by Richards^f and by Ono** 

 as his third alternative, /. <?., that the fungus can under the condi- 

 tions produced by the stimulant thrive more economically. 



The sensitivity of Pemcillinm on solution A is about equal to 

 that of Sterigmatocystis on solution C. 



Another question of interest is the stage in the growth at 

 which the CHCI3 is most potent. To learn this, series were run 

 with the optimum of CHCI3 placed in some when set up as before 

 and in others after the spores had been allowed to start. The 

 former were more prosperous (Table III) ; that is, the impulse given 

 at germination is more effective than one applied later, but even 

 after complete germination, the fungus responds, although in a 

 lesser degree, in the characteristic fashion. 



§ Loew. "Naturliche System der Gift Wirkungen." Munich, 1893, as quoted 

 by Davenport, Experimental Morphology, p. 7. 



II Hueppe f/. c.) suggests ihis vaguely. 



HZ. c. 



** L. c. 



