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THE PLANT WORLD. 
Describe the appearance of the smut on each, especially on the 
corn in different stages. 
Puff Balls. 
Every one probably knows what puff balls are. They grow on 
the ground or more rarely on rotten wood. A few species grow 
on the bark of trees. Observe different kinds, some small and 
some quite large. Describe the form of the different kinds ob¬ 
served, and the character of the outer surface. Note also the 
external difference between the nearly ripe and the very ripe 
plants. Cut open young ones and compare with the interior of 
ripe ones. How are the spores disseminated ? Puff balls are not 
poisonous if selected when they are white inside. 
Earth Stars. 
The earth stars ( Geaster ) are puff balls of a special kind. 
The outer part of the wall splits in the form of a star and curves 
back on the ground or below the plant itself. Compare different 
ones as to size, shape, the number of the divisions of the “ stars,” 
the difference in the character of the “ mouth ” of the inner wall, 
etc. Place some of the dry ones in water and note the results. 
Remove and dry again. 
The Agarics (Family Agaricaceae). 
These all have a cap, on the underside of which are narrow 
plates or “ gills ” in shape something like a knife blade which 
radiate from the stem, or point of attachment of the cap to wood, 
etc. 
The Common Edible Mushroom (Agaricus campestris ). This 
grows in pastures, lawns, on roadsides, and sometimes in culti¬ 
vated fields or meadows. The plant is two to four inches high, 
the cap two to four inches broad, the stem has a thin mem¬ 
braneous collar (the ring or annulus), the cap is white or, in 
some forms, gray or even light brown. The gills are first pink, 
then brown, and finally black. Note the color of the cap, and 
whether it is smooth, or scaly, etc., the thickness of the flesh, the 
odor and taste when fresh. Search for specimens in different 
stages of growth to see the difference in color of the gills. In 
