K. MiTAKE : On the Nature of the Sugars found in the Tubers of Arrowhead. 29 



1. It had a sweetisli taste. 



2. It did not reduce the Fehling's sohition directl}' ; after invertiou with 

 hydrochloric acid, it reduced very strongly showing the presence of non-reducing 

 sugai-s. 



3. It did not give the characteristic reaction of i^entose with phloroghicin 

 and hydrochloric acid. 



4. Molish- Udransky's reaction was positive. 



5. It did not give the characteristic colour reaction of Braun with picric 

 acid and caustic soda. 



6. It gave the characteristic fire red colour of ketose with resorciu and 

 hydrochloric acid (Seliwanoff's reaction). 



7. It did not give the characteristic colour reaction of free fructose with 

 ammonium molybdate and acetic acid. 



8. Upon oxidation with nitric acid of 1.15 sx>. gr., mucic acid was produced. 



9. From the filtrate of the mucic acid crystals, saccharic acid was separated 

 and detected as acid potassium saccharate by the usual method. 



10. It did not jjroduce any crystals with phenylhydrazine hydrochloride and 

 sodium acetate. When the mixture was Avarmed in a boiling water bath for 

 about 30 minutes, a few crystals of the yellowish crystalline glucosazone were 

 produced. After invertion, the gluco- and galactosazone were formed in abundant 

 quantity by heating for about 15 minutes. 



11. It rotated the x>lane of i)olarization toward the right both before and after 

 invertion ; though in the latter case its power was smaller than in the former case. 



From the above qualitative tests, it will be clear that the residue (I) under 

 examination contains some non-reducing sugai"s which are constituted from three 

 groups of glucose, galactose and fructose or two of these hexoses. 



b. Isolation of sucrose. 



The residue (I) was dissolved witli 95^ alcohol and evaporated to a syrap. 

 It did not show any sign of forming crystals of its own accord, even after one 

 week's standing. An attemi^t was then made to purify the syrux) by means of 

 basic lead acetate. The syrap was diluted with a sufficient quantity of water, to 

 which a favorable quantity of basic lead acetate solution was added and the 

 mixture well shaken. The fluid soon became turbid and after standing for a little 

 while, a small amomit of flocculent piecipitates was formed. After separating the 

 precipitates by filtration, a further quantity of basic lead acetate and ammonia 



