BIOLOGICAL BULLETIN 



OF THE 



firmrtne Biological Xaborator^ 



WOODS HOLE, MASS. 



EMtorial Staff 



E. G. CONKLIN Princeton University. 



GEORGE T. MOORE The Missouri Botanic Garden. 



T. H. MORGAN Columbia University. 



W. M. WHEELER Harvard University. 



E. B. WILSON Columbia University. 



flbanaging BMtor 



FRANK R. LILLIE -The University of Chicago. 



VOLUME XLVII. 



WOODS HOLE. MASS. 

 JULY TO DECEMBER, 1924 



