212 BOTANICAL GAZETTE [September 



a) The hot alcohol-ether soluble substances (sugars, amino 

 acids, amids, polypeptides, lipoids, etc.) increased by 8-9 per cent, 

 while the insoluble substances (proteins, starch, cellulose, ligno- 

 celluloses, etc.) were correspondingly diminished. The water 

 content of the ethylene treated and control tissues was the same. 



b) The lower soluble sugars (by direct reduction) were about 

 11 per cent more and the higher soluble sugars (by reduction after 

 hydrolysis) about 3 per cent less. The reducing power of the 

 alcohol-ether insoluble residue, after hydrolysis, was decidedly 

 less for the ethylene treated tissue; also, the cellulose content was 

 diminished by about 3 per cent. 



c) Amino acid plus amids were more, and the polypeptides 

 apparently less in the ethylene treated tissue. The protein con- 

 tent also was about 3 per cent less. 



d) Fats were much less abundant in the treated tissue. The 

 free fatty acid value was unchanged. 



3. The acidity of the ethylene treated tissue was not found to 

 be changed. 



4. Ethylene caused an increase of osmotic pressure, as measured 

 both by the freezing point and plasmolytic methods. 



5. The permeability was not sharply affected by ethylene, 

 although it was somewhat increased. 



6. Ethylene affected respiration, retarding both the CO, pro- 

 duction and the 2 absorption, but the respiratory ratio remained 

 practically the same. An exception to the preceding statement was 

 found in the case of the shortest exposure period (3 hours), in which 

 there occurred, apparently, an excessive production of C0 2 , thereby 

 increasing the ratio. 



I wish to acknowledge the many valuable suggestions of Drs. 

 William Crocker, of the Department of Botany, and Fred- 

 erick C. Koch, of the Department of Physiological Chemistry, 

 under whom the foregoing investigation was undertaken. 



University oe Chicago 



