Stonewort sp. A
7.6 km North, 1.7 km West of Hudson Bay
I believe this specimen is a member of the Chara genus, but at this time I cannot identify it to the species level (hence the sp. designation). Although it looks like an aquatic plant such as Ceratophyllum demersum (hornwort), Chara is a member of the Viridiplantae (green algae). Plants are believed to have evolved from some group within the Viridiplantae.
The branchlets bear globules (male reproductive structures) and nucules (female reproductive structures). The globules are orange and contain antheridial filaments whose contents become antherozoids (male gametes). The nucules are originally yellowish and contain a single oogonium whose contents become an egg cell (female gamete). Note that everything is encrusted with flakes of calcium carbonate.