It looks like an Arum maculatum. You can get cultivated ones, called Arum italicum, with lovely marbled leaves, but your plant is a native one - well, it is in the UK!

I agree it is an arum and its not related to calla.

I have the wild one in my garden and you get different markings on the leaves depending on which clump I look at.

I love these Arums they are lovely in the hedgerows around here. Am I right as kids we called them Lords and Ladies?

In Britain they have the most number of different common names of any plant.
Arum italicum in the plain green leafed form is found wild in various parts of Canada.

yes lords and ladies, priest in the pulpit, cuckoo pint as well as many others. A italicum has a creamy spadix whilst the A maculatum has a browny/burgundy spadix.

thank you Seaburngirl, cuckoo pint, yes I remember when I was little they called it that. Great information thank you :O)