FOOD AND OXYGEN IN CONTROLLING SEX 



105 



BRACHIONUS BAKERI 



During the spring of 1916 several collections of water and 

 sediment were made from the ponds in the vicinity of Middle- 

 town, Connecticut. The rotifer, Brachionus bakeri, was very 

 frequently found in these collections. Individual isolation ex- 



TABLE 2 



Mass culture experiments with Brachionus bakeri showing that when considerable 

 quantities of the green flagellate, Chlamydomonas , were added to the jar of water 

 that many male-producing females appeared but when only small quantities of 

 Chlamydomonas or none at all were added very few if any male-producing 

 females appeared 



