ILLUSTRATIONS. 



Page. 



Diagrammatic representation of inoculated turnip plant Frontispiece. 



Plate I. Fig. 1.— Bacterial cavity in turnip root. Fig. 2.— Bacteria in vessel 



of turnip root, highly magnified 20 



II. Cross section of lower part of rootof turnip plant shown in frontispiece. 20 



III. Cross section of turnip root higher up than PL II 20 



IV. Fig. 1.— Cross section of turnip root just under the leaves. sFig. 2.— 



Shows bacterial occupation of vessels of root at same level as fig. 1. 20 

 V. Fig. 1.— Vertical section of turnip root, showing bacteria in vessels. 



Fig. 2.— Vertical section of turnip root, showing bacteria in vessels. 20 

 VI. Fig. 1.— Cross section of turnip root, showing bacteria confined to a 

 single vessel. Fig. 2.— Cross section of turnip root, showing bac- 

 terial occupation of several vessels. Fig. 3.— Cross section of turnip 

 root, showing several vessels and many parenchyma cells occupied 

 by bacteria. Fig. 4.— Bacteria wedging apart parenchyma cells. 

 Fig. 5.— Bacteria wedging apart parenchyma cells. Fig. 6.— Bac- 

 teria of the black rot magnified 1,000 times; cover glass prepara- 

 tion \ 20 



VII. Figs. 1 and 2.— Cross sections of turnip root, showing occiipation of 



vessels -" 



VIII. Fig. 1. — Bacteria occupying intercellular spaces in the parenchyma 

 of the turnip root. Fig. 2.— Bacteria escaping from a small bundle 



into the surroundi^ng tissues 20 



IX. Figs. 1 and 2 illustrate early stages in the formation of bacterial cavities 



in the turnip root - - - - -^ 



X. Figs. 1 and 2 illustrate later stages in the formation of bacterial cavities 



in the turnip root -" 



XI. Margins of liacterial cavities, showing progressive destruction of the 



cell walls; more highly magnified than in PI. XI 20 



XII. Fig. 1.— Longitudinal section through turnip root near the cambium, 

 showing bacterial cavities. Fig. 2.— Small portion of the larger 



cavity of fig. 1, highly magnified 20 



XIII Figs. 1 and 2.— Additional details from the larger cavity in PI. XII, 



« 1 20 



fig 1 



