DESCRIPTIVE FLORA 



OSMTJNDACEAE (Flowering Fern- Family) 



Leafy plants with creeping rhisomes. Sporangia naked, globose, 

 usually with pedicels. Stipes winged at the base. 



OSMUNDA 



Fertile fronds or fertile parts of the fronds without much 

 chlorophyll, much contracted, and bearing short-pediceled, naked 

 sporangia. Fronds tall and upright, growing in large crowns from 

 thickened rootstocks, once or twice pinnate. Spores green. Ster- 

 ile fronds truly bipinnate. 



O. regalis. Royal Fern.' Very smooth, pale green. Sterile pinnules 

 13-25, sessile or short stalked. The fertile pinnules are at the summit 

 of the frond. Common in swamps and wet woods. May and June. 



O. Claytoniana, Interrupted Fern. The sterile fronds once pinnate 

 and the lobes entire. Covered when young with loose wool which' soon 

 disappears. The fertile fronds are taller than the sterile. Some of the 

 middle pinnae are fertile. The sporangia are greenish, turning brown. 

 Common in May in low ground. 



O. Cinnamomea, Cinnamon Fern. Sterile fronds once pinnate and 

 the lobes entire. Rusty woolly when young. Sterile fronds tallest, 

 smooth when full grown. The fertile fronds are separate, appear 

 earlier from the same rootstock, and soon wither;, they are twice pin- 

 nate, and covered with the cinnamon colored sporangia. Common in 

 swamps. 



EQTJISETACEAE (Horsetail Family) 



Rush-like plants with jointed and hollow steins arising from run- 

 ning rootstocks. Sheaths occur at the joint-like nodes. The fertile 

 stems bear terminal, cone-shaped structures composed of stalked 

 scales (sporophyllus) which bear sporangia beneath. Equisetum 

 is the only genus. 



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