BIOLOGICAL BULLETIN 



OF THE 



fiDarine Biological %aborator$ 



WOODS HOLE, MASS. 



Vol. XLIV March, 1923 No. 3 



CONTENTS y<f**" m \ i ' u % / 



Zeleny, Charles. The Temperature Coe 



*• , , #,J#U 4^023 



tficient oj avtieterffzygote with an 



Expression for the Value of a (S^rn^ial Difference 



in 1 erms oj an Environmental One . r 105 



Sivickis, P. B. Studies on the Physiology of Reconstitution in Plan- 

 aria lata, with a Description of the Species . . . u; 



Published Monthly by the 



MARINE BIOLOGICAL LABORATORY 



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Entered October io, 1902, at Lancaster, Pa., as second-class matter under Act of Congress of July 16, 1894. 



