192 BOTANICAL GAZETTE [SEPTEMBER 
Busse, WALTER. Bact. Studien iib. d. Gummosis d. Zuckerriibe. Zeitschrift _ 
f. Pflanzenkrankh. 7: 65-77, 149-155. 1897. Abs. in Centralbl. £ 
Bakteriologie und Parasitenkunde 3: 680-682. 1897. og 
SmiTH, Erwin F. The bacterial diseases of plants. II. Amer, Nat, 3o; : 
716-723. 1896. : 
The bacterial disease of sugar beets in the United States, Pre 
sented before the Society for Plant Morphology and Physiology in 1897. _ 
Ref. in Science 7: 118. 1898. z 
EXPLANATION OF PLATES XVI-XX. ; 
' PLATE XVI. e 
Leaves of healthy and diseased beets, as they appeared when brought in 
from the field. The three diseased leaves can readily be distinguished from 
the two healthy ones because of their blistered and crinkled surface. 
PLATE XVII, 
A diseased beet brought in from the field. The root is quite firm, none 
of the tissue being broken down. The leaves hanging down are quite dead 
and dry. The erect heart leaves are alive and show the characteristic 
crinkled surfaces. A 
PLATE XVIII. 
A, a diseased beet with the dead leaves removed. 8B, a healthy beet of 
same size and stage of growth, also with the dead leaves removed. 
PLATE XIX, 
A, cross sections through the crown of healthy and diseased bet 
4, healthy root. 4, diseased root, characterized by the black rings of vasculat 
tissue. : and 
&, cross sections through the central portion of the same diseased 
healthy beet roots. a, healthy root. 4, diseased root. 
C, cross sections near the tip of the same roots. 4, healthy r00t : 
diseased root. 
PLATE XX. figs 
A, longitudinal sections of the same healthy and diseased beet roots . 
ured in the preceding plate. a, healthy beet. 4, diseased root. «mila 
upward by the production of gas. 
B, the disease germ stained with carbol fuchsin ; 
graphed. : 
“imperfectly pho 
