So Little and Delicate

I dont know what to call this papery, delicate flower. I am presuming it is a flower as it has stamens. I thought I knew what it was but when I googled Albizzia, the flowers and the seed pods were nothing like this. And this didn't feature among the Albizzia stages posted on the website.

They have blown in drifts against the fence at the end of the street but examining the trees down the street has shown nothing like them.

I know Blipmate has blipped them before and thought they were Albizzia.
Can any clever Blipper out there  confirm this or name it correctly?

Another view of it in the extras.