64 THE BIOLOGY OF HYDRA : 1961 



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DISCUSSION 



WAINWRIGHT: Do you have any ideas concerning the site of 

 synthesis of the mesoglea? 



WOOD: In Hyman and other textbooks it is claimed that the 

 mesoglea comes from both epithelial layers. I really have little more 

 to add. It is always strictly extracellular and has no hmiting mem- 

 brane, as Dr. Hess has already pointed out. It corresponds to the 

 connective tissue of higher forms. I don't know exactly how it 

 arises. 



