Here'a another hydrangea inflorescence that's pretty nifty, an oak-leaved hydrangea.  This panicle (?) is nearly 18" long.  The large, showy sterile flowers stick out around the cylinder surrounding a cloud to tiny fertile flowers; no idea how many, lots.  They are opening bottom to top; you can see where the buds remain closed about half way up.  Lots of little black flies and beetles are crawling around in there; if you shake it the fall out in surprising numbers, but that's a little mean.