HOW TO KNOW FERNS 



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The Rattlesnake Fern 



globes which through a lens look like bunches of grapes. The 

 fertile frond may be single, simple, and leaf-like as in the little 

 Grape Fern or lobed as in the Moonwort 

 or triangular and compound as in the other 

 species. 



The Rattlesnake Fern is rarely recognized 

 as a fern, its large, triangular, much-divided 

 frond is light-green, lace-like and delicate; 

 it loves rich shady woodlands where there 

 is plenty of moisture. The Common Grape 

 Fern which also has a much-divided tri- 

 angular sterile frond is not more than a 

 foot high ; its fertile frond is on a separate 

 stalk and is so full of fruit that it looks 

 like a tiny grape cluster. This species is 

 found in moist meadows, pastures, and open woods. 



The Osmundas 

 There are three species of Osmurida; they are all large, hand- 

 some, rather coarse ferns and grow preferably in low ground and 

 swampy places. 



The Interrupted Fern (Fig. 1) has sterile fronds from two to 

 four feet high. Some of the largest fronds 

 have some pairs of the middle pinnae 

 changed in form and bearing fruit. Its 

 sterile fronds resemble very much the 

 next species. 



The Cinnamon Fern grows vigorously 

 and may be distinguished from the Inter- 

 rupted Fern by the tuft of rusty wool 

 which clings to the base of each pinna. 

 The Cinnamon Fern may have fronds five 

 or six feet high in favorable places. The 

 sterile fronds (Fig. 3) grow in a circle and 

 the fruiting fronds (Fig. 2) appear at the 

 center of the climip and do not look like 

 ferns at all. They are rusty in color because of the cinnamon- 

 colored spore cases and are club-shaped. 



The Royal or Flowering Fern is twice pinnate. The lower 

 pinnae looks like branches. The three or four upper pairs of 

 pinnae are changed in form and bear the fruit (Fig. 4). 



