BIOLOGICAL BULLETIN 



OF THE 



fiDarine Biological laboratory 



WOODS HOLE, MASS. 



JEfcitorial Statt 



GARY N. CALKINS Columbia University. 

 E. G. CONKLIN Princeton University. 

 M. H. JACOBS University of Pennsylvania. 

 FRANK R. LILLIE University of Chicago. 



GEORGE T. MOORE The Missouri Botanic Garden. 

 T. H. MORGAN Columbia University. 



W. M. WHEELER Harvard University. 

 E. B. WILSON Columbia University. 



Managing Editor 



C. R. MOORE The University of Chicago. 



VOLUME LI 1 1. 



WOODS HOLE. MASS. 

 JULY TO DECEMBER, 1927 



