PRODUCTION OF SPERMATOZOA IN ROTIFERS. 



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FIG. i. Formation of the functional spermatozoa in Brachionus mulleri. 

 A, young spermatids; B, older spermatids; C, young immature spermatozoa; 

 D, older immature spermatozoon; E, mature, motile, and functional spermatozoon. 



