FUNCTIONAL AND RUDIMENTARY SPERMATOZOA. 



331 



the heads showed their chromatin contents. Only the tails of 

 the rudimentary spermatozoa were found and they showed no 

 chromatin material in them when stained. Sketches of these 

 spermatozoa and tails are shown in Figs. 4 and 5. 



B 



3.HYDATIJTA 

 SENTA 



4.BRACHrOHUS 

 AMPHICEROS 



5.DIASCHIZA 

 STEREA 



FIGS. 3-5. Dimorphic spermatozoa and tails of three other species of rotifers. 

 A, larger normal and motile spermatozoa showing the head and the contained 

 chromatin; B, smaller, rudimentary and non-motile spermatozoon showing the 

 chromatin in the head; C, detached tails of rudimentary spermatozoa. (Drawn 

 with 4 mm. objective and number 2 ocular.) 



The spermatozoa of the other species of rotifers enumerated 

 in the former paper have not been reexamined because these 

 forms are not available at this season of the year. 



As the stained slides of the sectioned unlayed fertilized eggs 

 of Hydatina senta were available for study they were examined to 



