SALVINIACE^E. 2*71 



Synopsis of the Genera. 



1. Selaginel'la. Terrestrial. Stem slender. Leaves small. Spore- 



cases very small, axillary, some containing the orange-coloured 

 powdery microspores, and others with 3 or 4 larger macrospores. 



2. Iso'etes. Growing in water. Stem corm-like. Leaves elongated 



and rush-like. Spore-cases large, enwrapped by the spreading 

 bases of the leaves. 



1. SELAGINEL'LA, Beauv. 



S. rupes'tris, Spring. A little moss-like evergreen, grow- 

 ing on exposed rocks in dense tufts 1-3 inches high. Leaves 

 awl-shaped, with a grooved keel, and tipped with a bristle. 

 Spikes 4-cornered. 



2. ISO'ETES. L. QUILL WORT. 



I. eehinOS'pora, Durieu, var. Braun'ii, Engelm. (QuiLL- 

 WORT.) A small aquatic grass-like plant with a corm-like 

 stem, bearing 15-30 slender leaves. The large sporangia 

 axillary, partly enwrapped by the thin edges of the exca- 

 vated bases of the leaves, beset with small spinules. Lakes 

 and ponds, chiefly eastward. 



ORDER CXVI. SALVINIA'CE^E. 



Small floating moss-like plants, with branching axis, 

 covered with minute 2-lobed imbricated leaves. Sporocarps 

 in pairs beneath the stem, very soft and thin- walled, the 

 smaller ones acorn-shaped, containing a single macrospore, 

 the larger ones globose, containing several microspores. 



AZOLLA, Lam. 



A. Carolinia'na, Willd. Somewhat deltoid in outline, 

 much branched, of reddish aspect. Floating on quiet wat- 

 ers of Lake Ontario, not common. 



