Some species of fungi Armillaria are bioluminescent and may be responsible for the phenomena known as foxfire and perhaps will o' the wisp.

Foxfire is the term for the bioluminescence created in the right conditions by a few species of fungi that decay wood. The luminescence is often attributed to members of the genus Armillaria, the Honey mushroom, though others are reported, and as many as 40 individual species have been identified. On the suggestion of Benjamin Franklin it was used for light in the Turtle, an early submarine. In the novel Adventures of Huckleberry Finn by Mark Twain, the characters of Huckleberry Finn and Tom Sawyer use foxfire as a source of light in order to dig a tunnel.

For More Information:
Fungus K-12 Experiments & Background Information
Bioluminescence K-12 Experiments & Background Information

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