Bui. 1038, U. S. Dept. of Agriculture. 



Plate XL 





Vertical Sections of Healthy and Diseased Pecan Leaflets, 

 Frotscher Variety. 



Collected on August 2.i and 26, 1919, at Thoniasville, Ga. All figures at the same magnifieation. 

 X 540. A.— Healthy pecan leaflet cnllectcd at sundown, killed in Carney's fluid, and stained 

 with iodin to show the presence of starch in the palisade and spongy- ccUs. B. — Healthy 

 pecan leaflet collected in the morning, kiUcd in Carnoy's fluid, and stained with iodin to show 

 the absence of starch. C and D.— Pecan leaflets aborted with rosette, collected and treated 

 in the same way, respectively, as in the preceding two normal leaflets. Chloroplasts in both 

 night (C) and morning (D)'specimens were gorged with starch, and apparently no trans- 

 location had taken place during the night. Note also the enlargement of the cells in the dis- 

 eased material. Photomicrographs by the writer. 



