First squash blossom -- or, to be more precise, first male Green Racer zucchini blossom. A zucchini plant has separate blossoms for stamen and pistils. Here you see the stamen offering up pollen to a waiting world.
Here is a pistil-packing mama: a female Green Racer zucchini blossom (that's just the way it is in zucchini-dom). Behind the blossom, out of view, is a tiny zucchini. As I understand it, they don't develop much unless the blossom is pollinated. Hear that, bees? Get with it! People are waiting for their summertime green soup.