33(> 



BOTANICAL GAZETTE 



[NOVEMBER 



phosphoprotein phosphorus was spHt off from the insoluble frac- 

 tion (F3) by digesting a weighed amount (1-3 gm.) with i per cent 

 NaOH solution at 37-40° C. for 48 hours in an incubator, after 

 which the solution was neutralized with acetic acid and made up 

 to volume. The insoluble material was separated from the filtrate 

 by the use of the centrifuge. The filtrate obtained was tested for 

 phosphorus with magnesia mixture. The magnesium ammonium 

 phosphate precipitated out by standing overnight was dissolved, 

 and the phosphorus was reprecipitated as ammonium phospho- 

 molybdate and then titrated against a standard alkali (8). The 

 nucleoprotein phosphorus was estimated by the difference between 

 the total phosphorus minus the phosphoprotein and the inorganic 

 phosphorus in the two fractions (F^4-F3). The lipin phosphorus 

 was determined by taking an aliquot of the ether soluble fraction 

 (Fi). The ether was first driven off on a steam bath before acid 

 digestion and the percentage of this phosphorus was estimated in 

 the same way. 



TABLE V 



Different forms of phosphorus (percentage P) in seeds 



Material 



Inorganic P 



Lipin P 



Soluble organic P 

 Phosphoprotein P 

 Nucleoprotein P . 

 Total P 



0.132 



0.017 



0.034 

 1.790 



2.670 



4.649 



TABLE VI 

 Ratio of different P to total P (percentage P) in seeds 



Material 



Inorganic P 



Lipin P 



Soluble organic P 

 Phosphoprotein P 

 Nucleoprotein P. 

 Total P 



84 



37 

 73 



50 

 50 

 94 



Tables V and VI show the percentage of the different forms of 

 phosphorus. The data in these tables show that about 96 per cent 



