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DISCUSSION 



MUSCATINE : Have you ever turned green hydra sexual? 



LOOMIS: Only once, even though I have grown them in "sludgy 

 agar" and under the other conditions that make H. littoralis turn 

 sexual. That one time was after they had been neglected in a stag- 

 nant aquarium for a week or so. 



KLINE: Two questions. If you carry out the pC02 experiment 

 in the low bicarbonate medium, what kind of results do you get? 

 Also, I have heard discussion of a CO^-bicarbonate equilibrium in 

 which the two compounds were considered to be interchangeable. 

 Will you comment on this? 



LOOMIS: If the pCOo experiment is done in a low bicarbonate 



