The Fungus known as Bears Head Mushroom or Hericium Americanum is a member of the Hericium Genus (another notable member of that Genus is Lions Mane Mushroom), which is a genus of edible mushrooms that can be found growing naturally across North America and Asia.
This species, much like Lions Mane is renowned as both an excellent culinary mushroom, and a valuable medicinal mushroom. Due to its consistency and taste it can be used as a replacement for seafood in many recipes, and many individuals also take it as a supplement in powdered form. It's also one of the easiest mushroom species to grow, so is GREAT for beginner mushroom growers!
The physical characteristics of this species fruiting bodies are irregular, bulbous, tubercules (the best word to describe "tubercle" would be "blob") which are usually between 5-40cm in diameter, and are dominated by crowded, hanging, spore-producing spines. Fruit bodies and spines colour are white to cream, but can turn yellow-brown when older.