Species description:
Genus name derived from a Greek word meaning moss. Species name from the silvery appearance of the plants. Sometimes called "silver moss".

Comments:
Sometimes forms extensive colonies on the gravel of the flat roofs of high-rise buildings, attesting to the efficiency of its dispersibility as well as its tolerance of a seemingly inhospitable environment.

Distinguishing characteristics:
The silvery whitish-green, worm-like erect plants with nodding red sporangia are highly characteristic. Even with­out these sporangia, the glossy, worm-like, erect shoots are distinctive

Habit:
Forming silvery, whitish-green turfs, sometimes nearly white when dry; the erect shoots resembling erect worms.

Similar Species:
Plagiobryum zierii, an infrequent moss on calcareous cliffs and in tundra, resembles a very large B. argenteum but the silvery plants are often tinged with pink and the sporophytes have a very long tapered neck and are light brown when mature. B. calobryoides of subal­pine elevations also resembles B. argenteum but is larger arid the leaves tend to be less tapered and more widely spaced than in B. argenteum. B. bicolor is similar in size to B. argenteum and has similar sporangia but the plants are obviously yellow or dark green, with no hint of whitish­silver. Myurella julacea, which also forms dense tufts of silvery green, worm-like shoots, is usually confined to somewhat shaded, calcium ­rich sites and the leafy shoots are about Y2 the diameter of those of B. argenteum. In Myurella the shoots are generally branched and the leaves show no midrib.