At some stage it would seem that the Arum Lily was taken over to Australia, where it flourished and was subsequently declared a weed. In true Australian style [we do love you guys ;)] the government had strict laws enforced with respect to the transport and control of the plant.
What few may know (I certainly didn't) is that the boiled Arum Lily was, and perhaps still is, used by traditional medicine practitioners as a cure for headaches as well as a means to reduce skin inflammation.
Disclaimer: We don't suggest that you actually try using the plant for medicinal purposes... at least not before doing a truck-load of research on the Internet. :)
Tip: And, never utter the words "I read on the internet..." in the presence of your doctor.