1908] HASSELBRING— ASSIMILATION OF PENICILLIUM 189 



95° C. The reaction is due, as Nef" has sho^n, to the absorption 

 of water by the bivalent carbon of the ethylidene particles. The 

 reaction may be represented as follows. The dissociation of ethyl 

 sulfuric acid takes place thus : 



CH3CH,OSO,OH^CH3CH=+-OSO,OH 



r 



The sulfuric acid is regenerated and reacts with more alcohol to 

 give ethyl sulfuric acid^ or ethyl sulfate, while the ethylidene decom- 

 poses water to form ether thus : 



CH3CH<^ 



.CH3CH<^ 



If, in the first steps of assimilation, alcohol enters into combina- 

 tion with some substance of the protoplasm to form an unknown 



pound 



Ppm, then we should expect 



substances which increase ethylidene dissociation to affect the rapidity 

 of assimilation. It is immaterial whether the alcohol is first elaborated 

 mto sugar, glycerin, or some other substance, before it becomes a part 

 of the protoplasm, or whether it is directly taken up by the permanent 

 constituents of the cell. In either case it must combine with some 



combination must be regarded as 



assimilation 



An i 



grow 



solutions, would to some extent combine with alcohol and dissociate 

 into ethylidene; but an equal increase is obtained by the addition of 

 hydrochloric acid, and nitric acid shows an even greater increase in 

 ^ost cases; yet neither hydrochloric nor nitric acid combines with 



mixed 



stmiu 



any 



Fur- 



assimilation 



substance of the cell, then bodies w-hich dissociate 



ver}' easily should be 



We find, however. 



that potassium ethyl sulfate and ethyl nitrate, which dissociate to a 

 high degree, are valueless as sources of carbon when giwn alone, and 

 in all probabilitv^ cannot even be utilized by means of energy derived 



^^ Net, J. U., Dissociationsvomange bei den .\lkyiatheni der Salpetersaure, der 



und der HalocreTiwasserstoffsauren. Liebig's Annale 



fT« 



