CONTROL OF SEX BY FOOD IN ROTIFERS 



277 



The female rotifers were placed in a weak solution of Poly- 

 toma culture water which contained many Polytoma. Here 



TABLE 3 



Experiments with Diaschiza sterea showing that it was the food and not the culture 

 media that caused the males to be produced 



BXPEHIMENTS 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 

 10. 

 11. 

 12. 

 13. 

 14. 

 15. 

 16. 

 17. 

 18. 

 19. 

 20. 

 21. 

 22. 

 23. 

 24. 

 25. 

 26. 

 27., 

 28., 

 29.. 



Days 



RE.4RED AND CONTINUED IN STA- 

 BLE TEA CULTURE CONTAINING 

 POLYTOMA 



Fe- 

 males 

 isolated 



Estimated number of 

 offspring 



Days 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



4 



FEMALES REARED IN STABLE TEA 

 CULTURE CONTAINING POLY- 

 TOMA TRAN'^FERRED TO FIL- 

 TERED STABLE TEA CULTURE 

 WATER TO WHICH WAS ADDED 

 BOUILLON PED CHLf ROGONIUM 

 THAT HAD BEEN WASHED 



Fe- 

 males 

 isolated 



12 



12 



12 



12 



12 



12 



12 



12 



12 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



20 



Estimated number of 

 offspring 



80 

 100 

 100 

 106 



87 



81 

 112 

 112 



93 

 210 

 162 

 175 

 120 

 130 

 175 

 120 

 140 

 130 

 120 

 140 

 160 

 140 

 150 

 160 

 150 

 160 

 180 

 170 

 150 



20 



25 



25 



18 



37 



43 



12 



12 



31 



90 



87 



75 



60 



70 



75 



80 



60 



70 



80 



60 



40 



60 



50 



40 



50 



40 



20 



30 



50 



20 



20 



20 



15 



30 



35 



10 



10 



25 



30 



35 



30 



30 



35 



30 



40 



30 



35 



40 



30 



20 



30 



25 



20 



25 



20 



10 



15 



25 



