THE THEORY OF THE 



GENE 



BY 



THOMAS HUNT MORGAN 



Professor of Biology, California Institute of Technology 

 fm-merly Professor of Experimental Zoology in Columbia University 



Enlarged and Revised Edition 



NEW HAVEN 

 YALE UNIVERSITY PRESS 



LONDON . HUMPHREY MILFORD • OXFORD UNIVERSITY PRESS 



MDCCCCXXVni 



