I was excited to find such a cool liverwort along the Pony Bridge trail! There were hundreds of these a couple of miles from the beginning of the trail in the temperate rainforest. My field guide calls Conocephalum conicum "Snake Liverwort" and this site calls it Great Scented Liverwort. I wish I'd tried smelling it.
cf. Conocephalum conicum (Bryophyta: Marchantiopsida: Marchantiales: Conocephalaceae).
Cabin Branch Mine Trail, Prince William Forest Park, Prince William County, VA 24 February 2013
Observed hugging the damp rocks in a tiny "grotto" formed by a seep entering a culvert above the trail, 0.8 miles from the trailhead, descending switchbacks from the bench to the river bottom. Broad, flat leaves with distinctive markings. Deserves a closer look. Because Pojar calls it snake liverwort rather than great scented liverwort, I didn't know to smell the leaves, which "release a pleasant odour when crushed." (Pojar) Plants surrounding the grotto included goatsbeard/Aruncus dioicus, maidenhair fern/Adiatum pedatum, vine maple/Acer circinatum.