PLATE 52 



Fig. 3. Purticui uf dorsal cortex near the grooxe in the pedicel of Xicotiana, 

 showing the abscission process well under way. 



Fig. 2. (J roup of isolated cells washed off from end of a freshly abscissed 

 pedicel of Nicotiana. 



Fig. 3. Single isolated cell showing the thinness of the remaining cell 

 membrane. 



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