304 BULBS AND TUBEROUS-ROOTED PLANTS. 
This form of mold is common upon many plants, 
and at times is very destructive to root crops, as Turnip 
and Carrot. The Onion, another bulbous plant, is often 
attacked by the same or a similar gray mold (Botrytis). 
The multitudes of spores borne upon the tips of the 
branches germinate quickly, and, when lying upon the 
surface of a Lily leaf, will bore their tubes through the 
epidermis, as illustrated on this page. When once inside, 
the thread increases in size, and grows rapidly in length, 
branching and causing decay as it pushes along. After 
the Botrytis fungus has grown for a while it may pro- 
duce dark, hard bodies, by a peculiar twisting and knot- 
BOTRYTIS ON LILY LEAF, MAGNIFIED. 
ting of its threads. These dark masses, or sclerotia, 
remain uninjured through the winter, and when spring 
comes they produce peculiar trumpet-shaped outgrowths, 
as shown on Page 306, which finally give rise to multitudes 
of spores. These are set free, and, finding their way to 
the young Lily, produce the destructive gray mold again. 
These spores, by their large numbers and quick growth, 
show how it is possible for the Lily Disease to spread 
rapidly. The Botrytis is fond of moisture, and in a dry 
season the Lilies may generally escape; while, if the 
weather is damp, the destruction may be great. Mr. 
Kean suggests, as a remedy, ‘‘The planting of some 
other crop in alternate rows, which, with high and 
