The Ferns of Washington 67 



Spore-leaves at or near tips of branches, in some like the 

 foliage leaves, in others different and forming cone-like 

 spikes with or without pedicels. Sporangia all alike, 

 solitary in or very near the axils of the spore-leaves, 

 kidney-shaped, with thin tough walls ; spores very 

 abundant, all alike; thalli usually subterranean, with or 

 without chlorophyll. There is only the following genus. 



LYCOPODIUM. Club-moss. 



Description the same as for the family. (Greek lykos 

 a wolf, pons = a foot; apparently suggested by the 

 branched erect shoots of some species.) L. clavatum, L. 

 annotinum and L. inundatum are made into wreaths and 

 sold for Christmas decorations. 



A. Sporangia borne in axils of ordinary leaves; cones none; plant & to 

 t in. wide, very densely leafy. 



B. Leaves curved upward; steins usually 6 in. or less high; upper and 



lower leaves sterile. 1. L. selago. 



BB. Leaves spreading or reflexed; stems usually more than 6 in. high; 

 sporangia borne all along the stem. 2. L. lucidulum. 



A A. Sporangia borne in axils of modified leaves which are grouped in 

 special cones or spikes; plants either narrower or eJae leaves not 



extremely dense. 



C. Branches flat; leaves in 4 ranks, adhering to the stem. 



3. L. complanatum. 

 CC. Branches round; leaves in more than 4 ranks, not adhering to the 

 stem except sometimes in L. sitchcnse, 

 D. Erect branches apparently in tufts from a horizontal stem; 



leafy branches f£ in. or less wide. 4. L. sitchcnse. 



DD. Erect branches not in tufts; leafy branches often wider. 



E. Plant creeping with occasional erect branches, not at all tree- 

 like in its form. 

 F. Cones more than 1, on a long branch with leaves far apart. 



5. L. clavatum. 

 FF. Cones usually only 1, on an ordinary leafy branch. 



G. Leaves spreading; branches 2-forked, long; cones usually 



le than 1 in. long. 6. L. annotinum. 



< •(;. Leaves curved upwards; branches not distinctly 2-forked, 



not long; cones usually more than 1 in. long. 



7. L. inundatum. 



EE. Plant erect or nearly BO, roughly tree-like in its form. 



8. JL. obscurum. 



