THE AMERICAN BOTANIST 



57 



covers the shaded ledges. It is very impatient of both sunshine 

 and drouth. Cutting down the sheltering trees in its habitat 

 is usually sufficient to cause it to disappear. In the event of 

 drouth it simply casts its leaves and waits for another growing 

 season. In dry summers it is difficult tO' find the fern after 

 mid-July and even in years of more moisture it is probably the 

 first of the ferns to disappear. 



Eittle ledges and shelves of rock on which the fern delights to grow. 



When found, the cliff-brake is easily recognized. There 

 are no other ferns with fronds so delicate that grow in such a 

 habitat. A further distinguishing mark is found in the tw^o 

 kinds of fronds, the sterile being much broader and shorter 

 than the fertile though the latter are less than six inches long. 

 The indusium under which the sporangia mature, is broad and 

 thin and is formed from the margin of the frond. Some idea 

 of the size of the plant may be gained from our illustration 

 where the two^ round white spots near the right margin of the 

 picture are a silver quarter and a penny. 



