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Bul. 186, Bureau of Plant Industry, U. S. Dept. of Agriculture. PLATE IX. 
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| Fic. 1.—THE WoOOLLY-KNOT FORM OF HAIRY-ROOT ON THE CROWN OF A COLLINS APPLE 
1 TREE IN ORCHARD 1. 
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Fic. 2.—APPLE ROOT GRAFTS AND SEEDLINGS USED IN THE EXPERIMENTS. 
