ANIMAL PKOTEINS 47 



riety and abundance. Edestin contains no car- 

 bohydrate group while bacterial proteins con- 

 tain two and these gave us much trouble in our 

 earlier attempts to isolate the poison. 



Animal Proteins. 



We have prepared the protein poison from 

 a great number and variety of animal proteins, 

 such as egg-white, casein, serum albumin, se- 

 rum globulin, blood cells, muscle, brain, liver, 

 kidney, etc. In fact, we have found no true pro- 

 tein which does not yield the poison when split 

 up by the method given a two per cent solu- 

 tion of sodium or potassium hydroxide in ab- 

 solute alcohol. 



In beginning this work I expected to find the 

 simplest proteins in unicellular organism^. As 

 I have already indicated this expectation has 

 not been realized. The proteins of most simple 

 structure I have found in seeds and in the 

 casein of milk. Seeds contain the embryo ac- 

 companied by simple ^proteins and varying 

 amounts of fat and carbohydrate, also proteo- 

 lytic, amylolytic and lipolytic ferments. When 

 the seeds are placed under proper conditions of 

 temperature and moisture, the ferments begin 

 to act, the storehouses of foods are split into 

 available building blocks and growth begins. In 



