Stems: much branched, slender, prostrate and creeping, rather stiff, the branches ascending, sparingly forked. Leaves: uniform, spreading, five-ranked, rigid, linear-lanceolate, minutely serrulate, nerved below; spikes solitary at the ends of the branches, oblong-cylindric, composed of ovate bracts, each with a sporange in its axil; spores smooth on the basal surface.

A moss-like herb, with numerous tiny leaves completely covering the short branches, which terminate in dense, oblong spikes composed of small bracts, each one with a sac containing spores in its axil.

Lycopodium clavatum, or Creeping Club Moss, has extensively creeping stems and short, irregular, densely leafy branches. The leaves are much crowded, incurved, and tipped with tiny bristles, and the spikes grow in clusters of from one to four on long peduncles.

Lycopodium Selago, or Fir Club Moss, has thick, rigid, erect stems, the forked branches forming level-topped clusters.

Lycopodium alpinum, or Alpine Club Moss, has elongated, creeping stems, from which the densely clustered branches rise. The leaves are closely imbricated, and four-ranked, and the spikes solitary at the top of the branches.

Lycopodium sitchense, or Arctic Club Moss, is found at high altitudes, like Alpine Club Moss, which it closely resembles.

Lycopodium complanatum, or Trailing Christmas Green, is a most fascinating plant, with fan-shaped branches, which are forked, and covered with minute leaves with somewhat spreading tips; but the chief charm of the Trailing Christmas Green lies in the clusters of upright spikes, borne on long stalks, and which resemble Christmas candles.