CANCER RESEARCH This journal is sponsored by The .American Association for Cancer Research, Ine.; The Anna Fuller Fund; The Jane Coffin Childs l\iIemorid Fund far Medical Research; The Elsa U. Pardee Foundation; and The American Cancer Society.

Editwial Adoiaorg Board

W. U. G~RDNER SAMUEL GRAm I3k-m~ S. N. GREENE JESSE P. GXEENBTEIN E R I ~ HIRS~BFIRQ CHARLES HUQGINB ARTHUR Iirrzscasamr ALBERT L. LEH~NQER C. C* LITTLE

B-UDULW LUCKB

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Copyright 1952 by Cancer Rewar&. Inc.