Algae between the growing liverworts.

Thank you to Joe Metzger @joem50 who kindly ID my observation.

Here is his explanation "You have the same problem here as you did in http://www.inaturalist.org/observations/3704991 This is in the Non-Vascular Plants (Superphylum Thallophyta) with the Mosses, Hornworts, and Liverworts (Phylum Bryophyta) and more specifically with the Liverworts (Class Marchantiopsida). Sorry I can't get you farther but there don't seem to be any reproductive organs showing or I don't recognize them. One thing I did notice in both, you have multiple plant observations. If you didn't catch it, there is at least one species of Moss in the other one and in this one you have little bits of Stonewort which iNaturalist includes in Charophyte Algae (Phylum Charophyta), most likely in the Class Charophyceae, Order Charales and the Family Characeae which only has five Genera. You can see it clearest at the bottom in the center of http://www.inaturalist.org/photos/4301990 and there's a little showing at the top in the center of http://www.inaturalist.org/photos/4301989 and a piece going bottom to top on the left side of http://www.inaturalist.org/photos/4301992"