When I was a kid we called these H Bees because they have an H-shaped marking on their back. We would impress the neighborhood girls with our bravery by catching them with our bare hands with no fear of being stung. The girls of course had no clue that they were flies and not bees at all and had no stingers. When we opened our hands and showed them they would scream and run from the "bee" as it flew towards them. Thanks for the memory, enjoyed your post.