The Ferns of Washington 73 



branched. Leaves minute, very abundant throughout. 

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

 the foliage leaves, in others different and forming a small 

 terminal cone. Sporangia solitary on the spore-leaves 

 near their axils, of two kinds; microsporangia nearest the 

 branch-tip, containing many microspores; megasporangia 

 farther back, normally containing 4 large megaspores. 

 Thallus not projecting out of the spores. There is only 

 the following genus. 



SELAGIXELLA. Moss-fern. 



Description the same as for the family. (Diminutive 

 of Selago, an old name of Lycopodium; the plants 

 resemble small Lycopod turns.) 



A. Foliage lean s of two sizes, in two planes, the lateral ones much larger 



than those of the upper plane. I. S. Douglasii. 



AA. Foliage leaves all alike in size. 



B. Stems slender, pendent, often very long; leaves not crowded, spread- 

 ing when wet. 2. 5. sir uthioli odes. 



BB. Stems not slender, rigid; leaves crowded, rather appressed even 

 when wet. 

 C. Stems 4-12 in. long; leaves less crowded, about 8-ranke 1; sterile 

 branches less crowded; stem.- prostrate, not densely tufted. 



3. «S. rupestris. 

 CC. Stems 2-5 in. long, leaves much crowded, many-ranked; sterile 

 brandies crowded, incurved; stems densely tufted. 



3a. 5. rupestris densa. 



L Selaginella Douglasii (Hook.) Spring. (Plate 3, 



Fig. 6). 



Stems creeping, rooted at intervals, 3-12 in. long: 

 branches alternate, at nearly right angles to the stem, 

 2-6 in. long, branched again two or three times. Leaves 

 of the stem in two planes; lateral ones tV in. long, oval 

 obtuse, faintly veined; leaves of upper plane one-half as 



long, oval, incurved, ending in a short point. Spore- 

 leaves in distinct four-sided cones, closely appressed to 



