OBSERVATIONS ON THE CALIFORNIA VINE DISEASE 139 
The homogeneous form of the deposits may still persist in 
roots in the last stages of decay. Pierce observed in very 
decomposed roots corroded homogeneous matter. He says: “a 
microscopical examination of the decaying outer parts of the 
vascular bundles shows that the cell lumen is filled with a trans- 
lucent amber-like deposit. This persists after the decay of the 
cell wall, and presents rod-shaped, more or less irregular and 
eaten, amber-like casts.’ 
To sum up our microscopic observations in a few words: 
An examination of the various organs of a diseased vine— 
leaves, canes, fruit, roots—fails to reveal the presence of any 
parasitic organism. In all organs exhibiting signs of disease we 
find, however, a polymorphous gummous substance, containing 
proteid and tannic matters, that appears to be derived from 
starch. In the leaves chloroplastid degeneration precedes the 
occlusion of the cell lumen, or is arrested by it. 
ПІ 
The relationships of the California vine disease 
I said before entering on the description of the California 
vine disease that the symptoms shown by the various aérial 
organs had to be considered in conjunction with one another, 
and not singly, if this malady was to be identified with any 
certainty. Such a statement as this implies that the symptoms 
of the disease are also more or less common to other maladies ; 
and this upon examination we find to be the case. 
A comprehensive study reveals the interesting fact that the 
California vine disease has features in common with the diseases 
known as Folletage, Rougeot, Sun-scald, Brunissure, Shelling, 
and Tetranychosis. What their common characteristics are І 
shall now attempt to show, and this will be best accomplished by 
short descriptions of the related maladies. | 
Folletage —This disease may affect a vine either in part or in 
its entirety, is very rapid in its action, and, as 4 rule, fatal. 
Foéx tells us that all the vines in a vineyard are sometimes 
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"1 Pierce, М. В. Loc. cite, 53. 
