New Wildflowers: Mentzelia Species

These top two photos are of flowers growing
at Capulin Volcano, New Mexico.
They are some form of Mentzelia (blazing star)-
possibly Mentzelia multiflora,
but I have had a hard time finding a good match
in my flower books.

The bottom two are also a Mentzelia species,
Mentzelia nuda, or sand lily.
There was a great website on Kansas flowers
that showed me a good match.
These particular flowers were photographed in Nebraska,
near Chimney Rock,
but I saw them growing in Kansas as well.

Both types were totally new to me.
And gorgeous!