The Potatoe Plague. 83 
is twice as heavy as the healthy, which he attributes to the 
presence of a parasite. The loss of starch amounts to twenty 
per cent. There is present an azotized matter, having the 
same composition as fungi. All the chemical phenomena 
point to the action of such parasites, and not to spontaneous 
fermentation. Messrs. Girardin and Bidard, on the other 
hand, deny the presence of parasites. They find no other 
indication of their presence than what occurs in all cases of 
fermentation. ‘They regard the disease as the result of sim- 
ple fermentation, induced by the unfavorable season. They 
recommended perfectly rotten potatoes to be crushed in tubs, 
to be thoroughly washed, by which means the foul odor is 
removed, and then, after draining, to be pressed into cakes, 
which may be dried in ovens after the bread is withdrawn, 
and given to cattle. M. Durand attributes the disease to 
atmospheric causes, favored by local circumstances. He 
knew it in former years, when potatoes were grown in damp 
places. He denies the statement that the stems were always 
affected before the tubers, and he states that dryness and 
darkness are certain safeguards for the crop. Three hundred 
Hectolities have been thus preserved for a month without 
change, and yet they had not been very carefully sorted. M. 
Gerard adverts to the admitted fact that the disease attacked 
the potatoes between the 10th and 15th of August. He is 
opposed to the idea that animal or vegetable parasitism is 
connected with it as a cause, and he ascribes the disease to the 
presence of a brown matter “which seems to glue the starch 
grains together, and to prevent their separation.” He at- 
tributes its presence to unfavorable atmospheric causes, which 
caused the nutritive fluids to stagnate, and thus produced an 
alteration which ended in decay. 
A Mr. Spooner has published a pamphlet which is chiefly 
addressed to the question of converting potatoes into starch. 
