Green Dragon (Arisaema dracontium) and your Jack-in-the-pulpit (Arisaema triphyllum) are both members of the Arum family. Both have flowers on a spadix -- the central cylinder inside the "hood" -- and a spathe -- the "hood." The Jack-in-the-pulpit flowers are hidden by the closed spathe. You can see the Green Dragon flowers through the opening in the spathe in my photo. The Jack-in-the-pulpit spadix has a rounded top. The Green Dragon spadix tapers to a point outside the spathe. The leaves are quite different, but the seeds are nearly identical.
