Stinkhorn mushroom is notoriously phallus-shaped, so much so that the scientific name for the family is Phallaceae.    From Wordnik.com.  [The Blowfish Blog] Reference

Stinkhorns come in many shapes and sizes across the country, but they're most recognizable in giant phallic form they're in the Phallaceae family.    From Wordnik.com.  [NYT > Home Page] Reference