Christmas fern is below the others. 



How to Know the Ferns 



The ferns are classified by their methods of bearing their spores. 

 In some cases the spores are borne on fronds that do not resemble 

 the sterile fronds of the species in appearance. In others they are 

 borne on the lower sides of fronds that are quite similar to those 

 that bear no spores. In the latter cases, the shape of the fruit-dots 

 and the way they are blanketed, i.e. the shape of the indusium, 

 may afford the basis of classification. The following is an attempt 

 to define and illustrate the fern genera so that the beginner may 

 be guided into a more serious study of these beautiful plants with 

 the help of the excellent manuals which have been written by ex- 

 perts in fern knowledge. 



The Grape Ferns. Botrychium 

 There are six species of these which grow in moist woods or 

 swamps and they vary in size from the little Moonwort which 

 may be only two inches high to the Rattlesnake Fern which often 

 reaches the height of two feet. In the Grape Ferns the sterile 

 and fertile fronds are separate above but unite into one stem except 

 in the Common Grape Fern where the two have separate stems. 

 The fertile fronds have their pinnae reduced to little flattened 



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