460 R. H. A. PLIMMER AND W. M. BAYL1SS. 



- u j ; ;- f L : SUMMARY. 



, ,0-1., The whole of the phosphorus of caseinogen, except for a very 

 small residue, 'is converted into a soluble form by the action of trypsiu 

 in 24 hours. 



2. The curve for its rate of separation is exactly parallel to the 

 curve of the electrical conductivity during the first 7 8 hours ; its 

 rate of separation after this time is less rapid. 



3. The small insoluble residue is partly derived from the trypsin 

 and partly from the caseinogen and consists most probably of the 

 products of decomposition of nucleo-proteid. 



4. The " soluble P 2 5 " consists of inorganic phosphoric acid 

 35 per cent. and organic phosphorus, i.e. phosphorus combined in 

 an organic form, 65 per cent. 



5. The phosphorus of caseinogen is very slowly converted into 

 a soluble form by the action of pepsin. The quantity, thus changed 

 is only 70 per cent, in 149 days, and consists, except for a negligible 

 quantity of inorganic phosphoric acid, of organic phosphorus. 



6. Papain, in its action on caseinogen, is intermediate in power 

 between pepsin and trypsin. In its rate of splitting-off of " soluble 

 P 2 O 5 " and "soluble nitrogen" it resembles trypsin the more closely, 

 but it is much slower. 



It acts best in a neutral or faintly acid medium ; its action is slower 

 in a slightly alkaline medium and is almost inhibited by 0'5 per cent, 

 sulphuric acid and 0'5 per cent, sodium carbonate. 



7. Ovovitellin, containing lecithin, is very slowly digested by trypsin 

 in comparison with caseinogen. Only one-half of its phosphorus is 

 converted into a soluble form in 36 days. A similar quantity is 

 probably contained in the lecithin portion of the molecule. 



8. One per cent, caustic soda converts the whole of the phosphorus 

 of caseinogen into "soluble P 2 3 " in 24 hours. It resembles trypsin 

 very closely in its rate of action. 



9. The "soluble P 2 5 " produced by 1 per cent, caustic soda in 

 24 hours consists entirely of inorganic phosphoric acid. In the same 

 time the quantity of " soluble nitrogen " scarcely increases. 



