Stems much branched, slender, prostrate and creeping, rather stiff, 1—4 feet long, the branches similar, ascending 5—8 inches high, sparingly forked; leaves uniform, spreading, 5-ranked, rigid, linear-lanceolate, minutely serrulate, nerved below, spikes solitary or several at the ends of the branches, oblong, cylindric 1—1½ inches long, composed of ovate or ovate-cordate, short-acuminate and denticulate bracts, each with a sporange in its axil. In woods throughout the region, frequent. [Sidenote: =Lycopodium clavatum= L. _Running Pine._] Stems extensively creeping, 1—4 feet long with similar short, irregular ascending or decumbent, densely leafy branches; leaves much crowded, many-ranked, incurved, linear-subulate, bristle-tipped, the lower denticulate, the upper nearly entire or slightly decurrent on either side; spikes 1—4 on long peduncles; bracts membranous, roundish, and irregularly denticulate below. In dry woods and open grounds, rather rare in the region, observed only in the Selkirks around Glacier and Roger’s Pass. [Sidenote: =Lycopodium sitchensis= Rupr. _Arctic Club-moss._] Stems prostrate, 8—12 inches long, on or a little beneath the surface; sending up frequent branched stems which form compact masses of vertical, compressed branches 2—3 inches high, with occasional stronger, spike-bearing branches; leaves lanceolate with a broad base, spreading and curving upwards, thick, entire, acute, in five rows on the branchlets; the spikes nearly sessile. On grassy alpine slopes 6000 feet and upwards in the Selkirks, especially in the region about Glacier. [Sidenote: =Lycopodium complanatum= L. _Trailing Christmas-green._] Stems extensively creeping, with erect or ascending reinform or fan-shaped branches, several times forked above with crowded flattened branchlets; leaves minute, overlapping, flattened, 4-ranked, the lateral row with somewhat spreading tips; peduncle slender, 2—6 inches high, forked, bearing 2—4 linear-cylindric spikes, bracts broadly ovate, acuminate, with pale irregularly cut margins. In mossy woods at the lower altitudes, more or less frequent throughout the region, especially in the Rockies. [Sidenote: =Lycopodium alpinum= L. _Alpine Club-moss._] Stems prostrate, 8—20 inches long on or near the surface of the ground, forming numerous, several times branched clusters 2—3 inches high with glaucous leaves, and occasional stouter, compressed spike-bearing stems, extending above the others; leaves 4-ranked, erect, flattened, those of the lateral rows two to three times larger than those intermediate; spikes sessile, few, ½—¾ of an inch long. In alpine meadows, on slopes, and in open woods throughout the region from 6000 feet upwards. SELAGINELLACEÆ _Selaginella Family_