Western Fairy Slipper (White-flowered Form) in Washington Park

I have been looking for this and hoping to find it for three or four years and finally have seen it, though I can't take credit for finding it.  A friend from Montana was in our area for the tulip festival and visited Washington Park in Anacortes.  She found it and gave us careful directions as to where she had seen it.  It was growing as a single plant in an area where there were quite a few of the normal form.

This is Calypso bulbosa var. occidentalis fma. nivea, the pure white form of the Western Fairy Slipper.  It lacks all the pink-purple color of the normal form and the lip entirely lacks the brown markings, though there is some yellow-green color at the back of the lip.  In the pictures it is evident that it was a wet and rainy day when we went to see it and we came home very wet and muddy, but happy.