186 Alfred J. Eivavt : 



solution had a sweetish taste, was dextro-rotary, and gave a strong 

 reduction with Fehling's test. 



The precipitate from the carbon dioxide was suspended in water, 

 sulphuretted hydrogen passed through and filtered. The filtrate 

 was evaporated to dryness, and the nearly colourless gummy residue 

 dissolved in water and filtered. It was sweetish in taste, laevoro- 

 tary, and gave a strong reduction with Fehling's test. 



Hence the sugars produced are a mixture of dextrose and levu- 

 lose, and probably in equal proportions since the original solution 

 showed a slight laevorotation. 



In a further experiment Pasteur's solution was added to a watery 

 extract from photo-oxidised " xanthophyll,'' and a drop of water 

 containing lU to 20 yeast cells. The tubes were sealed, and kept 

 at 25*^0. In one week, yeast cells were abundant, and actively 

 budding, carbon dioxide was formed, and the filtered liquid gave 

 the iodoform test for alcohol. The sugars are, therefore, ferment- 

 able by yeast. 



In the above experiments the " xanthophyll " used contained not 

 only " xanthophylloids," but also other extractives. Accordingly 

 pure preparations of xanthophyll were prepared by slight modifica- 

 tions of the methods used by Willstatter and Mieg. (Lieb. Ann. 355 

 .1. 1917). Chopped dry grass leaves (4 kilogrammes) were ex- 

 tracted with alcoholic potash. The filtered liquid was treated with 

 excess of ether and a separation effected by the addition of water. 

 The red ether extract was washed with water, dried with anhydrous 

 sodium sulphate, concentrated, and petrol ether added. The red 

 precipitate which forms, was dissolved in hot acetone and filtered 

 after cooling and standing, leading a white solid, and a dark almost 

 black liquid (orange red when dilute). To this, twice its volume of 

 methyl alcohol was added, and on standing in darkness and out of 

 contact Avith air, pure xanthophyll crystallizes out, and can be 

 finally washed with petrol ether. 



The xanthophyll obtained was exposed to photo-oxidation as dry 

 films in tubes in a current of air, and in the form of a fine emulsion 

 in water. No trace of reducing or non-reducing sugar could be 

 detected after oxidation whatever the method used. In the first 

 experiments traces of formaldehyde seemed to appear, particularly 

 when the photo-oxidation was rapid. It was found, liowever, that 

 the methyl alcohol used for precipitating the xanthophyll yielded 

 traces of formaldehyde when exposed to sunlight. On removing 

 this source of error no formaldehyde could be detected as a product 

 of the oxidation of xanthophyll. It is worthy of note that pure 



