These are the bright yellow sori of the Polypody Fern, a small fern about 10" tall usually, most often found growing in mats on the top of limestone boulders. In this species, the spore dots (or fruitdots) appear only on the upper 2-3 inches of the frond, so that's all you're seeing here.
Each 'sorus' or clump of spore cases ('sporangia'), contains microscopic spores, which provide for the fern's reproduction. On the Male Fern they tend to be dark by this time of year, and very obvious.
Finally, this is the fertile frond of a Sensitive Fern. This species grows an entirely separate frond with the sori or spore cases on it, in these tiny round balls, which by this time of year would be brown and dry. They'll stand up above the snow right through the winter.
It occurs to me now that I've collected these photos that they'd be much more effective if they were paired with pictures of the entire fern fronds; maybe I'll do that someday. In the meantime, I remain fascinated with ferns. All these pictures except the last were taken in our yard, where I have a small fern garden along the old stone fencerow.
P.S. To answer a question from Alain on the last post, also on ferns, here are pictures of the Green Spleenwort and the Maidenhair Spleenwort. I haven't found a noticeable difference in size, but the first clearly has a green stem, while the second has a dark, brownish or purplish stem.