BIOLOGICAL BULLETIN 



OF THE 



flDarine Biological laboratory 



WOODS HOLE, MASS. 



VOL. LI 1 1 AUGUST, 1927 No. 2 



CONTENTS 



CRABB, EDWARD DRANE. Anatomy and Function of the Rcprodn<tiv<' 



System in the Snail, Lynmcua stagnalis 

 appressa Say 55 



CRABB, EDWARD DRANE. The Fertilization Process in the Snail, 



Lymncca stqgnafis appressa Say 67 



RATCLIFFE, H. L. Mitosis and Cell Division in Euglena spiro- 



gyra Ehrcnberg 109 



COE, WESLEY R. The Nervous System of Pelagic Nemerteans 123 



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 Entered October 10 ,1902. at Lancaster. Pa., as second-class matter under Act of Congress of July 16 .1894 



