Here is a photo of the emerging bush bean plant
They are called the cotyledon ( also called the seed leaves) It is the embryonic leaf within the seed. Above are the first set of “True Leaves” . Drop that line when you are showing friends your garden. They will be impressed!
Some of you have mentioned that some of your beet, spinach and carrot leaves have not germinated. The extraordinary amount of rain could have either rotted the seeds or washed them away. When in doubt, replant. You are creating a succession planting of the item.
You can actually harvest some of these as micro greens if you would like or wait a little longer for a more bountiful portion. use a scissors and cut a small patch leaving an inch at the base for regrowth.