i84 



BOTANICAL GAZETTE 



[march 



tically all the spores had germinated and had produced germ tubes 

 50 to 100 p- long. This is clear proof that the potassium ethyl sulfate 

 is not poisonous in the concentrations used, but also that it is not a 

 suitable source of carbon. This is more fuUy brought out in table VI- 

 The cultures with potassium ethyl sulfate behaved as before, while 

 those with suKate to which alcohol was added gave a yield comparable 

 with that obtained when alcohol alone was given. These cultures, 

 like the alcohol cultures, remained pure white and produced no 

 spores. 



concentrations ranerincr from 



m 



per 



50^*^ to 0.91^"^ per 50*=^ proved absolutely valueless as a source of 

 carbon, although like potassium ethyl sulfate it did not inhibit germi- 

 nation at these concentrations. In a series in which the ethyl nitrate 



place. 



iource of carbon and nitrogen, no growth iook 

 funsrus able to break ud the nitrate by means 



energy 



of ethyl nitrate failed to produce an increase of yield over pure alcohol. 



contrarv 



that ethyl nitrate is mildly 

 spores in cultures with et 



— X ^ ^ 



This is also shown by the fact that 

 ate germmated two to three days 



cultures. ' 

 germination 



be 



nitrate. The cultures produced no spores. 



Ethyl acetate.—WhilQ the esters of alcohol with mineral 



carbon 



source 



but 



in stronger solutions it becomes a poison, as appears from tables IX and 

 X. The mineral solution used here was of the same composition as 

 in the alcohol cultures* 



Each flask received o . 



Numbo' 



X 



3 



4 



5 



No mineral add 



13 



14 



14 



15 



TABLE IX 



'Mi> 



CH3COOC2H5-0.05 GM. per Uter. 



o . 0O4nHN'03 

 12 



12 



12 

 X2 



12 



o.oc4»H,S04 



0.004 



wHO 



II 

 II 

 II 



12 

 13 



