There are numerous Sycamore trees growing all over our neighborhood. During winter time when their leaves are all gone they are left with these dense puffy balls hanging like ornaments. However, when they fall and open up, we see a whole bunch of cottony seeds explode out of them. I carefully picked out one seed and made a slide for me foldscope. This is how it looks up close. I noticed that they have small thorns. These probably are there for attaching the seeds to things passing by. These nasty little puffballs also seem to cause a lot of allergies out here!