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2. O. Claytoniana Clayton’s O. Interrupted fern 
Lvs. 3-l'2dm. long, 1 -2.5dm. wide, pinnately divided, the If Its. 
deeply pinnately divided into broad rounded lobes. Sporangia on 
2-4 pairs of If Its. in middle of If. 
Moist woods, common. 
Sugar Creek ; Moore. 
Nfd. to N. C., Minn, and Mo. Also in India. 
May- June. 
3. O. cinnamomKa Cinnamon fern 
Spore-bearing lvs. 4-8dm. tall, 8- 12cm. wide, clothed with 
brown wool, withering after shedding spores. Green lvs. 8-12dm. 
tall, 15-25cm. wide, pinnate, the pinnae deeply pinnately lobed ; 
If Its. veiny, stiff. 
Swamps ; very rare here. 
Eldora {fide C. B. Frazier), Steamboat Rock (coll. Reppert). 
Native all round the n. temp. zone. 
May. 
Order 4. Fieicades 
Sporangia minute, scarcely visible, on the backs of ordinary lvs., 
or covered by inrolled If Its., or on slightly contracted green If Its., 
usually in groups called sori (singular sorus), often with a mem- 
branous covering called indusium. 
Family 9. Polypodiaceae) Fern family 
Characters of the Order. 
1. Poly podium Polypody 
(Poly, many; pous, foot; from the branching rhizome) 
Lf. l-2dm. long, 4-6cm. wide, simply pinnate, the If Its. attached 
to midrib by a broad base. Sori circular, large, without indusium. 
Lvs. shedding from rhizome by a neat scar. 
1. P. vulgare Common P. 
Our only species. 
On rocks or rocky bluffs, rare here. 
Eldora. 
All over N. America, Europe and Asia. 
July- Sept. 
2. Phegopteris Beech fern 
Small ferns with delicate annual lvs. Spore dots small, round, 
without indusium, borne on the back of a vein, not marginal. 
