93 



and is secretion stimulated when animals are trapped? Is the 

 EiKjlcna that inhabits old bladders immune to these enzymes or 

 are such old traps no longer functional? 



In spite of the work of the investigators quoted, together with 

 that of Buesgen, Cohn and others, we have before us today, in a 

 modified form, to be sure, what Brocher nearly twenty years ago 

 called 'Le Probleme de TUtriculaire.' 



My thanks are due to Professor F. E. Lloyd for his unfailing 

 help. I am indebted to him also for permission to reproduce figures 

 I, 2, 4-8, 10 and II. 

 McGiLL University 

 Montreal, Canada 



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