witches' butter

witches' butter (usually uncountable, plural witches' butters)

1. Any of several gelatinous fungi which are generally yellowish (resembling globs of butter) or black (resembling black butter), including those of species:
   1. Tremella mesenterica, a yellow, gelatinous fungus (yellow brain fungus, golden jelly fungus).
   2. Dacrymyces, a genus of yellow jelly fungus often confused with Tremella.
      1. Dacrymyces chrysospermus (orange witch's butter).
   3. Exidia nigricans, a black, gelatinous fungus.
   4. Exidia glandulosa (black witch's butter).
2. A yellow slime mold (Fuligo septica).
3. Certain species of Nostoc of blue-green algae, especially Nostoc commune, that form a brownish gelatinous mass when wet.

• witch's butter

• witch's egg
• witch's hair

• witches' butter on Wikipedia.Wikipedia
• “witch”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.