Thought it would be easy just to add a photo...there are a few different ones in the database though, so thought i'd better check first :)

Found growing in the wild in Ontario Canada.

found it!!

Arisaema atrorubens

Well, good for you, solved your own mystery!

So... I'm not exactly following this exchange. Arisaema atrorubens is just a synonym for Arisaema triphyllum, which is the accepted name (and the most commonly used) for the same plant. So it's Arisaema triphyllum.
:confused:

Quote from Connecticut Botanical Society site, "While some sources divide New England's Jack-in-the-pulpits into three species (Arisaema triphyllum, A. atrorubens, and A. stewardsonii), most modern authorities lump them all into A. triphyllum. "
http://www.ct-botanical-societ...

According to the USDA plant database (http://plants.usda.gov) there are four subspecies:
Arisaema triphyllum ssp. pusillum
Arisaema triphyllum ssp. quinatum
Arisaema triphyllum ssp. stewardsonii
Arisaema triphyllum ssp. triphyllum

And Flora of North America, only three:

http://www.efloras.org/florata...