75 



therefore, another portion of the extract was first treated with a mixture 

 of ether and absolute alcohol in which only fructose is soluble and 

 then divided into two portion, one, the liquid, containing the dissolved 

 matter, and the other the remaining insoluble portion. On testing with 

 resorcin and concentrated hydrochloric acid the dissolved portion gave 

 the proper cherry-red coloration of the sugar while the other did not. 

 Though saccharose also takes the same coloring with the above reagents, 

 yet it seems to me that some fructose not saccharose must be 

 present in the petiole, because, if saccharose be present in it, the un- 

 dissolved portion would also take the same red coloring as saccharose 

 is not soluble in the mixture of ether and alcohol. 



The fact that the soluble mannane is present in the cells of the 

 leaf, makes it very probable to suppose that it plays to some extent 

 the role of starch in this Araceous plant but the question whether 

 mannose is really the first product of the assimilation process or not, 

 can not yet be solved but I hope to settle the question by further 

 investigations. On the other hand the natural occurance of mannose 

 in the petiole of this Araceous plant is evidently of highly physiological 

 interest so it is the first time that mannose has been found in plants. 



In conclusion, I wish to express my hearty thanks to Prof. Dr. 

 0. Loew of the Imperial University, who has given me kind suggestions 

 and taken much interest in this investigation. 



Chemical Laboratory of the Harris Science School, 

 Doshisha, Kyoto, September, 1896. 



