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PHARMACEUTICAL BOTANY 



SUBDIVISION 1. LYCOPODINE^E OR CLUB MOSSES 



Small perennial, vascular, dichotomously branched herbs with 

 stems thickly covered with awl-shaped leaves. The earliest forms of 

 vascular plants differing from ferns in being comparatively simple in 

 structure, of small size, leaves sesssile and usually possessing a single 

 vein. Except in a few instances the sporangia are borne on leaves, 

 crowded together and forming cones or spikes at the ends of the 

 branches Homosporous. 



FIG. 156. Lycopodium clavatum. (Gager.) 



Family I. Lycopodiaceae, including the single genus Lycopodium 

 with widely distributed species. The spores of Lycopodium clavatum 

 are official. 



Family II. Selaginellaceae, including the single genus Selaginella 

 with species for the greater part tropical. Plants similar in habit to 

 the Lycopodiaceae but showing heterospory. 



Family III. Isoetaceae, including the single genus Isoetes whose 

 species are plants with short and tuberous stems giving rise to a tuft 



