62 



FORMATION OF DEFENSIVE FERMENTS 



point of attack from which to initiate their decom- 

 position. 



Some examples which, in the form of curves, repre- 

 sent the results obtained from the disintegration of 

 mixtures of plasma, or serum, with some substrate 

 (albumen or peptone), may serve to illustrate the 

 above statements. 



(i) A dog, whose serum did not decompose pep- 

 tones, was given 0*5 gr. of casein by means of a 

 subcutaneous injection on November 25 and 29 and 

 December 4. The blood used in the experiment 

 below was withdrawn on December 6. The polari- 

 scope tube was filled with a mixture of 0*5 c.c. of 

 serum, 0*5 c.c. of silk-peptone solution (10 per cent.), 

 and 7 c.c. of normal salt solution (see fig. i). 



o 



0,10 



0,7J 



Q2O" 



Holt; s- 



6 7 



FIG. i. 



(2) A dog was given repeated subcutaneous in- 

 jections of crystallized albumen obtained from seeds 

 of the gourd. The last injection was made on 

 December 8, 8 gr. of albumen being injected. The 

 serum was examined on the following day. For this 

 experiment i c.c. of serum was mixed with 0*5 c.c. 



