Wolfsbane


 * You may be looking for the novel of the same name.

Wolfsbane, also known as monkshood — and by the Latin name aconitum napelltis — was an Earth plant. When he first encountered them, Harry Sullivan did not recognise their characteristic buttercup-like leaves, and their blue-purple, bell-like flowers.

The Fourth Doctor told Harry that they were poisonous to wolves. (PROSE: Wolfsbane)