CHESTNUT BLIGHT 9 
white. The term “fans” has been applied to describe these thin 
spreading plates of fungous growth. (Fig. 7.) 
When well established the fungus fruits. The reproductive 
bodies formed, corresponding to the seeds of plants, are known as 
spores. Two types of spores are produced from pustules, which in 
dry weather resemble orange or red-brown pinheads dotted over 
the surface of the cankers. (Fig. 8.) During damp weather certain 
pustules produce tiny yellow, coiling, hairlike tendrils, called spore 
horns (fig. 9), which are composed of myriads of spores about the 
size of bacteria. These spores are borne within the pustule in such 
Vigure $.—Fruiting bodies of the chestnut-blight fungus 
numbers that when moist they are forced out in a slender serpentine 
mass, much as paste is squeczed from a tube. Spores of this type 
are sticky when moist. They adhere to insects, birds, and animals 
coming in contact with them and thus may be carried long distances. 
Rain dissolves the dry spore horns and washes the spores into worm- 
holes and wounds to start new cankers. 
Pustules producing the second type of spore differ from_ those 
producing the first in that during wet weather they are dotted with 
very small openings rather than surmounted by spore horns. The 
openings, which are often at the end of small protuberances (fig. 
8), are the mouths of flask-shaped structures. Within the flasks 
the spores are borne, definitely arranged in groups of eight 2-celled 
spores. Each group is inclosed in a thin, transparent, club-shaped 
