212 S. \V. GEISER. 



PLATE III. 



FIGS. 31-33. Outline drawings showing the forms assumed by the chro- 

 matin in the development of the head of the spermatozoon. 



FIGS. 34-35. Outline drawings showing the developing spermatozoa arrang- 

 ing themselves at the periphery of the spermatozeugma that is forming. 

 FIG. 36. Tangential section of the wall of a spermatozeugma, showing the 

 closely-packed arrangement of the spermatozoa in the spermatozeugma. 



FIG. 37. Spermatozoa from a nearly-ripe spermatozeugma. 



