Hi, this is the first year that I have planted Zinnias. I've been collecting the dried heads of the flowers for seeds for next year but am confused as to what part is the seed. I'm very new to gardening so my knowledge of what is called what is very lacking. When I pull apart the head of the Zinnia am I supposed to be saving the longish things attached to the heads (not the petals) or the small seed like things that I've found in some? I'm confused because when I planted them the seeds were long and fragile and I didn't have any of the seed like things in the package like what I have found in some of the heads.

thanks!