I spotted one of these on the first day of summer. It's called Farewell to spring, Clarkia dudleyana, in the Evening Primrose family. Named after explorer William Clark and a botanist named Dudley. For a look at what I've been writing lately, check out my blog at blackoaknaturalist. This blog is like a diary or extemporaneous journal from which I choose material for more developed, illustrated essays.
Still hoping to end up with a book of essays titled A Crack in the Sidewalk.