Can anyone here point me to pictorial information and descriptions for hybridizing and germinating peony? Other resources for learning the basics?

I have a tree peony that has self seeded. Now that I've found the offspring (currently 3 that I recognize) I'd like to investigate hybridizing purposefully. It would help me to see pictures of the flower parts, fertile seed, germinating seed, etc.

For example, I'm actually concerned that I could be unknowingly weeding out juvenile seedlings before they get their first true leaf.