Bull 19. Div Veg. Ptiys Sl Path., U. S Dept. Agriculture. 



Plate III. 



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PfiotoTniorogrrnp/i of sections to shou' Later sf ages of stL^monose 

 prodhLoed fry aphi/l piawtures omd. thrips. 



IIn1;^h..» TX^>;^< n»'D... 



