DISEASE-RESISTING FUNCTIONS OF THE BLOOD 321 



near relative of the recipient; since different human strains may 

 behave toward each other as do different species. Fortunately the 

 operation of transfusing blood is neither excessively painful nor 

 accompanied by untoward after effects to the donor, and persons 

 can always be found who are willing to undergo the discomfort 

 involved for the sake of restoring a fellow-being to health. 



