LrcopoDiA.CE^. (club-moss family.) 601 



-I- +- Leaves of the flattened stem and branches unequal. 



6. L. dendroideum, Michx. Stem erect (6' -12'), clothed with scattered 

 appressed subulate and entire leaves, simple below, bearing above numerous 

 forking and spreading fan-like mostly compressed branches ; lower row of leaves, 

 and sometimes the upper, shorter, the lateral ones spreading ; peduncles short, 

 bearing one or more cylindrical spikes ; bracts spreading, ovate, acute, crenate 

 on the margins. (L. obscurum, L.). — High mountains of North Carolina, and 

 northward. 



7. Ii. Carolinianum, L. Stem creeping, pinnately branched, naked 

 and rooting beneath ; upper leaves short appressed, the lateral ones widely 

 spreading, lanceolate, acute, entire; peduncle slender (6' -12' high), clothed 

 with scattered subulate leaves, and bearing a single linear spike; bracts" ovate, 

 acuminate, spreading. — Low pine barrens, Florida, and northward. — Stem 2' - 

 8' long. 



8. L. complanatum, L. Stem long and creeping, the numerous erect 

 branches successively forking into many linear crowded flattened branchlets ; 

 leaves minute, subulate, imbricated in 4 rows, the lateral ones slightly spread- 

 ing; peduncles with minute scattered leaves, slender, beai-ing 2-4 erect cylin- 

 drical spikes. — Woods along the Alleghanies, and northward. — Stem 2° - 10° 

 long. 



2. SELAGINELLA, Bcauv. 



Fructification of two kinds, either in the same or separate axils ; one kind as 

 in Lycopodium, the other with sporangia containing few (mostly 3-4) larger 

 spores. Spikes 4-angled. 



1 . S. rupestris, Spring. Stems rigid, densely clustered, erect or spread- 

 ing, much branched; leaves (grayish) subulate, rigid, rough-fringed on the mar- 

 gins, bristle-pointed, closely imbricated in many rows; spikes linear, nearly 

 sessile. — Dry sand ridges in the pine barrens, and on dry rocks, Florida, and 

 northward. — Stems 2' -3' high. 



2. S. apus, Spring. Stems prostrate, creeping, slender, branched ; leaves 

 scattered, unequal, the lateral ones larger and widely spreading, 2-ranked, 

 ovate, acute or obtuse, membranaceous, denticulate on the margins ; the others 

 smaller, acuminate, and appressed ; bracts of the short sessile spike similar to 

 the leaves. — Low shady woods, Florida, and northward. — Plant whitish. 

 Stems 3' -9' long. 



3. PSILOTUM, E. Brown. 



Sporangia of one kind sessile, globular, opening at the apex into 2-3 valves, 

 and filled with very minute powdery spores. 



1. P. triquetrum, Swartz. Stem forking, compressed, the branches 3- 

 angled ; leaves very minute, bristle-like ; sporangia spiked, 3-celled, the cells im- 

 perfectly 2-valved. — East Florida. 

 61 



