CONTRIBUTIONS TO EMBRYOLOGY, No. 28. 



CYTOPLASMIC STRUCTURES IN THE SEMINAL EPITHELIUM 



OF THE OPOSSUM, 



BY J. DUESBERG, 



Adjunct Professor of Anatomy, Faculty of Medicine, University of Liege, Belgium, 

 Research Associate, Department of Embryology, Carnegie Institution of Washington. 



With two plates and five text-figures. 



47 



