This first one is our native (eastern) Maidenhair fern, Adiantum pedatum. Pedatum would have to do with feet in Latin, so there seems to be some sort of disconnect in the name, except that I can see a resemblance to ladies tresses, probably more like braids of some sort. These grow in our woods across the road in great numbers on the shaded, northfacing hillside amongst the trilliums and gingers. It is one of my favorite places to walk in the spring when I can steal a little time from chores. I always go there on my birthday because I know, except on really cold springs, everything will be up and gorgeous, including the yellow flowered violets that grow along the creek. Maidenhair fern seems to be one of the more difficult to transplant to a different region. If you're looking for one, find a garden center that has locally grown ones if you can and you'll probably have happier ferns.
This next one is Adiantum pedatum var. aleuticum. It is from the far north, as the name suggests and so far seems to be happy here on a cold hillside, growing under a huge magnolia where it never gets any direct sun and very little light at all. I always marvel at plants that can thrive in such conditions, what with the need for photosynthesis and all. I guess either more light gets to them than I think or they have just evolved to survive in those conditions. The leaflets on this one are larger and coarser than the eastern maidenhair, though it still has the wiry stems. All of the maidenhairs ferns have a tall(ish) stem where the frond come off from the top, as opposed to the fronds just coming out of the ground. It is sort of hand shaped with the fronds being like the fingers. Though I should try and explain that since it really isn't clear in the pictures.
The last Maidenhair fern that we have in the garden is a southern maidenhair fern which is sometime listed as a zone 7 and which I grew inside in a pot for many years thinking it wasn't hardy here. We have had it growing in the shade of a crabapple to the north of the cactus bed for about 5 years now and it increases each year. The light is brighter there which may be something it is adaped to given its southern roots. It is a more delicate fern with tiny, sort of triangular leaflets on the same wiry stem. The stems on all maidenhairs ferns seem to be easily broken, so it you have dogs that run through the garden, these may not be the best choice for you, but I wouldn't be without them as they add a lightness and delicacy to the garden that most other ferns cannot approach. Almost forgot - the name of this one is Adiantum capillus veneris.