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INDIANA MUSHROOMS
           Bird's Nest Fungi
These tiny "mushrooms" grow from wood or woody debris.  Cyathus striatus
and
Crucibulum laeve are woodland species that can also be found in urban
areas, sometimes growing by the hundreds in mulch, often together.  The
cup-like "nest" holds tiny "eggs" (called periodoles), which are little spore sacs.  
The periodoles of some species are dispersed by raindrops, hence the common
name "Splash Cups".