More than thirty years has passed since Metchnikoff1 proposed his now famous thesis of phagocytic immunity. The stimulus furnished by his work was of inestimable value to the subsequent rapid development of immunology; but the original views held by Metchnikoff and some of his followers have been modified in the light of more recent investigations. It is now generally appreciated that certain humoral factors are necessary even for the phagocytic reaction. As stated by Topley and Wilson,2 "The views of the extreme 'cellular' school... are obsolete in their original dogmatic form." Despite present teachings as to the complex nature of immune reactions, the principle of phagocytosis in the original restricted sense has enjoyed periodic recrudescence in its practical applications to therapeutics.
About five years ago, stimulated by the results of Hanes3 in the treatment of pruritus ani by the local injection of hydrochloric acid, Burr Ferguson4