Page:Parsons How to Know the Ferns 7th ed.djvu/160

 and have secured a hold that enables you to stand up and examine at leisure the suspicious patches, your heart bounds with delight as you get a near view of the fringe of blue-green, leathery fronds which flatten themselves against the gray cliffs. Apparently only the plants that grow under specially favorable conditions are able to develop fronds that attain a length of five or six inches. Only in what must have been almost constant shadow, under the shelving rocks, directly above the lake and refreshed always by its moisture, did I find these really