Known as:  Indian Rhubarb, Umbrella Plant
Latin Name:  Darmera peltata (Saxifragaceae)
Poisonous Parts:
Symptoms: Vomiting, drooling, diarrhea, abdominal pain, cramps, swelling around the mouth, difficulty breathing.  May cause tremors, heart and respiratory and/or kidney problems which are difficult for an owner to detect.
Treatment: Unless your cat is unconscious or having convulsions, induce vomiting.  Get immediate veterinary assistance.

Images courtesy of Brousseau California Flora Photos.