37 



a fresh saline extract of leucocytes and placed under toluol 

 in an incubator. 



After two weeks' digestion in this fresh saline extract of 

 leucocytes there was still some residue present. This was 

 filtered off, the filtrate saturated with (NH 4 ) 2 SO 4 at the boiling 

 temperature and an abundant proteose precipitate obtained, 

 which dissolved easily in water forming a dark brown solution. 

 On heating this solution an abundant precipitate came down 

 which dissolved to a slight extent on further heating and which 

 became more marked on cooling. This same result was ob- 

 tained with picric acid. With trichloracetic acid a precipitate 

 was formed which was not completely soluble on further heat- 

 ing, and which became more marked on cooling. The same 

 results were obtained with potassio-mercuric iodide. With 

 HNO 3 an abundant precipitate was produced, which disap- 

 peared on heating and returned on cooling. The solution was 

 dialyzed till free from sulphate and evaporated speedily to 

 dryness at 40 C. As it was thought that the undigested 

 material might be collagen, it was boiled with water but the 

 supernatant liquid gave only a slight reaction for protein. 



To determine if this residue was digestible it was treated 

 with a fresh active alkaline trypsin mixture and placed in an 

 incubator. After 48 hours no digestion had taken place, and 

 on saturation with (NH 4 ) 2 SO 4 , no precipitate came down. 

 Most of the undigested material dissolved in Na^Og from 

 which it could be precipitated by acidifying the alkaline solu- 

 tion with HC1. This material consisted chiefly of hematin as 

 seemed evident also from its color. 



Summary of Results of Procedure D. i. Osseoalbumoid, 

 on digestion with a dried extract of leucocytes, prepared by 

 the method of Opie, yielded osseoalbumoses. 



2. An aqueous solution of the osseoalbumoses produced 

 by the leucocytic proteolysis of osseoalbumoid did not give 

 a sharp heat-precipitation test. However, after the addi- 

 tion of picric acid, trichloracetic acid, nitric acid, or potassio- 

 mercuric iodide, a sharp proteose test was obtained. 



3. Neither the extract of leucocytes nor the autolyzed 

 leucocytic material gave a heat-precipitation test. 



