1915] 



II. 1 RYEY—ETH YLENE 



203 



on account of the probability of a great variety of hydrolyzable 

 polysaccharides present. 



The amount of reducing sugars in the soluble fraction is con- 

 siderably greater in the treated tissue, although the results of sample 

 II are inconsistent. Again, after hydrolysis, the treated tissue 

 still shows more reducing sugar, but the difference is less pro- 

 nounced, which means that the higher soluble carbohydrates, such 

 as the disaccharides, are really less in this tissue than in the un- 

 treated. One seems justified in saying that the ethylene treated 

 tissue has about n per cent more of the lower, and about 3 per cent 



TABLE II 

 Carbohydrates 



* Hydrolysis 5 hours. 



less of the higher soluble sugars than the untreated. The reducing 

 power of the alcohol-ether insoluble fraction after hydrolysis is 

 clearly less in the treated tissue. The polysaccharides, which are 

 likely to be present and which are capable of yielding reducing 

 sugars by this acid hydrolysis, are starch, ligno-celluloses, galactans, 

 pectins, etc. Microchemical tests show that very little starch is 

 present in either tissue. The reducing sugars, therefore, are largely 

 from other polysaccharides. An examination of the drawings of 

 fig. 2 will aid in interpreting the differences found. Around the 

 four leaf traces, mechanical tissue is considerably more abundantly 



