FIXATION OF COMPLEMENT 91 



specific manner, i.e,, without amboceptor and comple- 

 ment, through several agencies. Thus, if the cor- 

 puscles be placed in plain water, haemolysis will occur, 

 and likewise through the addition of various substances, 

 such as snake venom, tetanus toxin, etc. Specific 

 haemolysis differs from non-specific in that it will 

 take place in an isotonic fluid such as physiologic salt 

 solution. 



In haemolysis there is no actual solution of the cell. 

 The process consists rather in a disturbance of the os- 

 motic equilibrium between the cell contents and the 

 surrounding medium. The haemolytic amboceptor 

 combines with the stroma of the cell, increases the 

 permeability of the latter, setting free the haemoglobin 

 into the surrounding medium. Bacteriolysis is de- 

 pendent upon a similar mechanism, and differs from 

 haemolysis in that it is practically invisible to the naked 

 eye. 



The blood of most animals usually contains a cer- 

 tain amount of natural haemolysin for the red cor- 

 puscles of other animals. Thus, human blood-serum 

 possesses a considerable natural haemolytic power for 

 sheep's corpuscles. This normal haemolytic power can 

 be greatly increased artificially by injection of the 

 blood-corpuscles of one animal into another, so that 

 very high dilutions of the second animal's serum will 

 haemolyze the corpuscles of the first, in the presence of 



