’ New Yorx AGRICULTURAL EXPERIMENT STATION. 171 
When the rot is confined to the outermost fleshy scale, as is 
frequently the case, the affected bulbs are called “slippery onions.” 
Some of these are to be found in any season, but they are rarely 
so abundant as to cause material loss. 
Microscopie examination of the rotten tissue shows entire ab- 
sence of fungi, but there are swarms of a medium-sized motile 
bacillus which is without doubt the immediate cause of the rot. 
When the rot commences at the bottom of the bulb the whole 
lower part is soft and eventually the entire onion becomes in- 
volved. The rot spreads upward through all of the scales simul- 
taneously. Bulbs so affected show a profuse growth of Musarwum 
about the base and the rotten tissue is filled with the Fusarium 
hyphee mingled with the previously mentioned bacillus. Although 
the presence of the bacillus is sufficient to account for this base 
rot it seems probable that the Fusarvwm aids materially and in 
some cases it may be the primary cause. | 
By inquiry among onion growers it was learned that there is in 
nearly every season a small amount of loss from rot which usually 
appears in the form of “ slippery onions,” although both the center 
rot and the base rot have long have been known. ‘The note- 
worthy fact in connection with the rot in 1898 is the unusually 
large amount of center rot. 
The rot was noticed by farmers when the crop was harvested in 
August, but the full extent of the trouble was not realized until a 
month later when the crop was sorted for market. At first it was 
attributed to injury from hail which fell on July 30; but later the 
hail theory was rendered untenable by the discovery that there 
was considerable rot in fields which had not been struck by the 
hail. Probably, the wind accompanying the hailstorm was a much 
more important factor in the rot. In nearly all of the onion fields 
the tops were much broken by the wind. 
Among stored onions kept reasonably dry the rot progresses very 
slowly, but wet onions rot rapidly, especially if the temperature 
is high. 
