Flobberworm

The flobberworm is a ten-inch, toothless brown worm which eats vegetation, especially lettuce and cabbage. It is a fairly boring creature, with a Ministry of Magic classification of only X (the lowest possible ranking, or "boring").

Each end is identical to the other, each end chews vegetation and from both it exudes mucus which is sometimes used to thicken potions. It moves very little and prefers to live in damp ditches.

Contrary to the claims of Draco Malfoy and his gang, which were designed to attack Rubeus Hagrid and his quality as a professor, flobberworms do not have teeth and do not bite.

Flobberworms are apparently edible and flobberworm fritters are sometimes served for lunch at Hogwarts School of Witchcraft and Wizardry, much to the dismay of the student body.

The flobberworm is notable for being one of the few living creatures capable of being summoned with the Summoning Charm.

History
After losing his nerve during the Hippogriff decable in his first Care of Magical Creatures lesson during the 1993-1994 school year, Rubeus Hagrid had his third year students raise flobberworms for a term. The exercise was completely pointless, as they prefer to be left alone and to do nothing. They didn't require much care, although they seemed unable to control how much food they needed as they will die if overfed. For the students' final exam, they simply had to monitor a flobberworm and make sure it was alive at the end of the hour appointed for the lesson.

In potions
Flobberworm mucus is green and sticky and is used to thicken potions. Flobberworm mucus is a vital ingredient in the Wiggenweld potion.

In the 1996-1997 school year, Severus Snape's detention for Harry Potter included scraping flobberworm mucus off the desks.