STUDIES ON IL^MOLYSINS. 87 



and it has perhaps some practical significance, viz., that in the fre- 

 quent injection of various curative sera into man and animals, the 

 possibility of autoanticomplement formation should be borne in 

 mind. Another case belonging here has previously been described 

 by us the disappearance of part of the complements in a rabbit 

 poisoned with phosphorus. In connection with this the following 

 observation of Metalnikoff (1. c.) is of interest. He was immunizing 

 a rabbit with spermatozoa and noticed that in consequences of a 

 purulent process which developed during the course of the immuni- 

 zation, the complement which activated the spermotoxin disappeared 

 from the serum and did not reappear for a considerable time. 



These isolated observations seem to indicate that the com- 

 plements can disappear during pathological conditions in conse- 

 quence, perhaps, of a more rapid destruction or of a slower formation. 

 The same holds true for the immune bodies (amboceptors) which 

 in bacteriolysis as well as in haemolysis have at least as great a sig- 

 nificance as the complements. Which of these two factors prevails 

 in any single case cannot be decided by any general rule, but each case 

 must be examined separately. Only through such investigation will 

 we gain an insight into the nature of "natural predisposition" and 

 its changes, " increased resistance/' "loss of resistance," etc. 



