66 BULLETIN OF THE BUSSEY INSTITUTION. 
was covered with dilute sulphuric acid and allowed to stand over 
night before filtering. The filtrates from the lead sulphate were 
neutralized carefully with dilute ammonia and evaporated to thick 
syrups upon water-baths. The residues were taken up with 10 cc. 
of a mixture of equal parts of alcohol of 95 percent. and water ; 
the solutions were filtered, warmed to expel the alcohal, and tested 
with the phenylhydrazin acetate reagent, No mannose-hydrazone 
was obtained neither directly nor on trying to reeryenel tae the 
precipitates by means of warm alcohol. 
A much larger quantity of the syrup, amounting to some 500 cc., 
was treated with the basic lead acetate, and three successive pre- 
cipitates were obtained. ‘They were decomposed separately by 
passing carbonic acid gas through water in which they were sus- 
pended. The filtrates from the lead carbonate were evaporated 
to dryness, the residues were taken up with diluted alcohol (3 : 1) 
and evaporated to syrups which were mixed with water and, after 
filtration, tested with the phenylhydrazin acetate reagent. No 
mannose-hydrazone was obtained. 
As regards the molasses, so called, the liquid portion of the 
magma was allowed to drain away from the solid particles of 
sugar, and the thick syrup thus obtained was diluted with twice 
its volume of water. Meanwhile, the solid sugar from which the 
thick syrup had drained away was dissolved in 500 ce. of water 
and commingled with the diluted syrup just now mentioned. The 
volume of the mixture amounted to about 800 ce. To it were 
added 1 or 2 cc. of the solution of basic lead acetate. The 
heavy, brownish-white precipitate produced was filtered off, 
washed with water, and decomposed by means of a current of © 
carbonic acid. After the lead carbonate had been removed by 
filtration, the liquid was evaporated to dryness on a water-bath. 
The residue was taken up with 3-5 cc. of diluted alcohol (8:1) — 
that was slightly warm, and the filtrate was evaporated to a thick 
syrup which was taken up with 3 cc. of water; 16 drops of the 
phenylhydrazin acetate reagent were added to this aqueous solu- 
tion and a yellowish amorphous precipitate fell at once. Some 
crystals of dextrose-osazone appeared in this precipitate after 
long standing, but no mannose-hydrazone was detected. 
To the filtrate from the first precipitate produced by the basic 
lead acetate a new quantity of this reagent was added and a 
