comradejon 的最愛

I use this genus & species name but wonder if it is actually something different? The leaves are very similar to the pink, but they are all about half the height, and seem to have a slightly but consistent difference in shape of flower with the large open hole in the front of the pouch.
Any ideas on ID?

Two Trillium species growing side by side (T. undulatum on the left and T. erectum on the right) in the Breadloaf Wilderness in the Green Mountain National Forest. This observation focuses on the plant on the left.

Dutchman's breeches has a rather limited distribution in the Pacific Northwest, but extends westward to a few locations in the Willamette Valley and northern Oregon Coast Range.

In the past the western plants have been separated as var. occidentalis; it would be interesting to see if molecular data would support any separation. Rydberg originally separated occidentalis from the eastern and midwestern plants on the basis of coarser foliage, spurs that are longer and more diverging, a more prominent crest on the inner petals, and underground parts "more gruinose and not scaly".