Wildflowers: Purple hedgehog

I like to browse my old photos. Always find something new. This time at the background of Erigeron peregrinus I noticed some oddity. Any idea what this could be?
The shot was made on 2010.07.17 at 9662 m high meadow.

 

I see some resemblance to this.

http://en.wikipedia.org/wiki/Trifolium_arvense

 

Thank you, Ron! Not Trifolium, as the later has pubescent sepals.
I thought a little, what kind of head-like flowers are blooming in August
in our meadows. As I can guess, this might be Agastache urticifolia
at the very early stage. In a week or two it should look like these:

 

The inflorescence on the first image in your thread does not look like Agastache urticifolia or any kind of Lamiaceae I heard of.

 

Well, I have to wait till August to check it, now. If, of course, summer happens this year. We still have about 5 m of snow pack up there.

 

I think I figured this out: it is Phleum alpinum in making.
Here are more developed plants: