SELAGINELLACEAE. 15 



Selaginella struthioloides (Presl) Underw. Stems weak, soft, 30-180 

 cm. long, often more or less pendent, much branched; leaves about 1 mm. 

 long, linear-lanceolate, loosely imbricated, not bristle-tipped. 



On trees along the coast, often hanging in great masses; Vancouver Island 

 to the southern boundary of Oregon. First found at Nootka Sound. 



Selaginella rupestris (L.) Spring. Stems loosely tufted, 10-25 cm. long, 

 prostrate or ascending, much branched; leaves closely imbricate, narrowly 

 lanceolate, ciliate margined, channeled on the back, each tipped with a slender 

 white awn, 0.3-0.5 mm. long; spikes quadrangular, 1-1.5 cm. long; bracts like 

 the leaves but the awns shorter and the margin more ciliate. 



On rocks, often very abundant. Hieronymus has recently distinguished 

 from true S. rupestris numerous new species and subspecies. The form common 

 in our limits is 5. sartorii oregonensis Hieronymus. 



Family 7. ISOETACEAE. Quillwort Family. 



Plant aquatic, usually submersed or sometimes growing on 

 moist soil, consisting of a short, two or three-lobed fleshy stem 

 with a dense tuft of fibrous roots and a compact cluster of rush- 

 or grass-like leaves; sporangia in small lobes enclosed in the 

 bases of the leaves; spores of two kinds, large (megaspores) and 

 small (microspores) . 



22. ISOETES. Quillwort. 



Stem a fleshy corm rooting just above the base, surrounded 

 above by the swollen bases of the awl-shaped linear leaves; 

 sporangia large, enclosed in the bases of the leaves, those of the 

 outer leaves with megaspores, those of the inner with micro- 

 spores; the sides of the sporangia more or less covered with a 

 fold of the inner side of the leaf base (velum). 



Plants terrestrial, in muddy places; leaves with stomata. 



Stems 3-Iobed; leaves setaceous; velum complete. /. nuttoUii. 



Stems 2-lobed; leaves stout, rigid; velum incomplete. /. inaritima. 

 Plants aquatic, often in deep water; stems bilobed. 



Stomata none; leaves rigid. /. pi peri. 



Stomata present; leaves slender. /. echinospora. 



Isoete.-. nuttallii A. Br. Growing in wet places; leaves 15-50, slender, 

 bright green, 6-20 cm. long; megaspores grayish, warty or rarely nearly smooth; 

 microspores brown, papillose. 



Vancouver Island to Oregon. Apparently rare, but quite inconspicuous. 



Isoetes maritima Underw. Terrestrial in salt marshes; trunk slightly 

 bilobed; leaves 8-15, rigid, 2-5 cm. long; megaspores densely spinulose, the 

 spines blunt but rarely confluent; microspores smooth, white. 



Known only from salt marshes at Alberni, Vancouver Island, Macoiin. 



Isoetes piperi A. A. Eaton. Leaves 10-20, 5-8 cm. long, somewhat spread- 

 ing, rigid; velum incomplete; megaspores with low distinct warts; microspores 

 smooth or nearly so. 



Green Lake, Seattle, Piper. 



