192 Alfred J. Eivart : 



The dark blue green colour, therefore, apj^ears to be due not to an 

 excess of chlorophyll, but rather to the more compact character of 

 the tissue, and it appears as though chlorophyll develops most 

 rapidly when its normal functional activity can be exercised. The 

 conclusion seems also justified that the carotin supplied at least 

 a part of the carbon and h^'drogen for the construction of chloro- 

 phyll. 



The spontaneous decomposition of chlorophyll. 



Twenty pounds of grass leaves were extracted with absolute 

 alcohol, and separated with two litres of petrol ether. After wash- 

 ing with 80% alcohol, the petrol ether solution containing a little 

 alcohol and a trace of water was placed in a completely filled bottle. 

 The percentage of chlorophyll was estimated by diluting against 

 a sample of pure chlorophyll and comparing under the spectroscope. 

 The bottle was sealed and kept in darkness for one year. On open- 

 ing and diluting a sample the colour was strongly yellowish green 

 instead of pure green. The solution was divided into four parts. 



One part was evaporated to dryness, and treated with cold 

 absolute alcohol. This left behind a large amount of a brownish 

 white Avaxy film, readily soluble in petrol ether. The solution was 

 diluted down to a dilute solution of known strength, in which only 

 the red band of chlorophyll was visible. This indicated that per 

 gram of the original chlorophyll only 0.54 gram remained. 



To the second portion of the petrol ether solution twice its 

 volume of absolute alcohol was added, and sufficient hot water to 

 bring about separation. After standing three days in darkness 

 the subnatant liquid was deep yellow, and a layer of solid red par- 

 ticles was present between the two liquids. These were collected 

 and washed. They consisted mainly of xanthophyll, with a little 

 carotin. 



The third portion was evaporated to dryness in the form of a 

 film lining a large tube. It weighed 4.452 graan. After soaking 

 in cold absolute alcohol for several days, the brown waxy film re- 

 maining was washed and dissolved in petrol ether. On evaporat- 

 ing, it weighed 1.309 gram, and on incinerating after warming 

 with a drop or two of nitric acid it yielded 6.8 per cent, of ash as 

 magnesium oxide. According to Willstatter, the phyllins (glauco- 

 phyllin and rhodophyllin have the formula (C3iH„oN4Mg(COOH2) 

 which represents 7.1% of ash as magnesium oxide. 



The fourth portion was agitated with a little water, the petrol 

 ether allowed to evaporate and the residue distilled. Tlie distillate 

 contained distinct traces of formaldehyde. 



