354 THE PLANT PHYLA 
Phylum XI. LEPIDOPHYTA. The Lycopods 
Minute gametophytes, producing branching, small-leaved, 
rooted sporophytes. (Living species about 
700, but very many extinct.) 
Class 25. LYCOPODINEAE. Lower Lycopods. Isosporous; 
leaves without ligules. 
Order LycopopraLes. Gametophytes much larger than 
the spore. 
Family 1. Lycopodiaceae. Ground Pines. Dendroid, 
evergreen plants.—Lycopodium. 
Family 2. Psilotaceae. 
Class 26. LEPIDODENDRINEAE. Higher Lycopods. 
Heterosporous; leaves with ligules. 
Order SELAGINELLALES. Small plants; stems not thicken- 
ing. 3 
Family 3. Selaginellaceae. Club Mosses. Moss-like 
plants bearing terminal cones.— 
Selaginella. 
Order LEPIDODENDRALES. Paleozoic and Mesozoic trees, 
long extinct. 
Family 4. Lepidodendraceae; 5, Bothrodendraceae; 
6, Sigillariaceae; 7, Pleuromoiaceae. 
Phylum XII. CYCADOPHYTA. The Cycads 
Minute gametophytes developed in naked seeds produced by 
the large, leafy-stemmed and rooted sporophytes; 
sperms motile. (Living species about 140, but 
very many extinct.) 
Class 27. PTERIDOSPERMEAE. Seed Ferns. Paleozoic, 
fern-like plants, long extinct. 
Order PrerIpOSPERMALES. With characters of the class. 
Family 1. Lyginopterideae; 2, Medullosae; 3, Clad- 
oxyleae; 4, Protopityeae; 5, Araucari- 
oxyleae. 
Class 28. CYCADINEAE. Common Cyeads. Mesozoic to 
present plants with pinnate leaves. 
Order CycapaLes. With the characters of the class. 
Family 6. Cycadaceae. Mostly tropical trees with 
staminate cones only.—Cycas. 
