BIOLOGICAL BULLETIN 



fiOarine BtolOQical Xal?orator^ 



WOODS HOLE, MASS. 



Vol. XVIII April, 1910 No. 5 



CONTENTS 



PAGE 



Twelfth Annual Report of the Marine Biological Laboratory 213 



KiiiKiiAM, William B. Ovulation in Mammals^ with Special 



Reference to the Mouse and Rat.,. 245 



Cole, Leon J. Description of an Abnormal Lobster 



Cheliped, 252 



Harvey, E. Newton. Methods of Artificial Partheno- 

 genesis 269 



Heath, Harold. Pelagosphcera^ a Larval Gephyrean 281 



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