14 POLYPODIUM INCANUM. IIOARY POLYPODY. 



of creative time. Some of the earlier botanists regarded this 

 species as a " parasite," but many modern ones do not regard it 

 as even an epiphyte, in the sense of attaching itself to trees, 

 believing that it grows only among moss or other decaying 

 material which is collected on the trunks and branches. In 

 Mississippi, where I have seen it abundantly on oaks, it was 

 always associated with moss, as is the specimen here illustrated, 

 which was kindly cut for us from the roof of a house in South 

 Carolina, by Dr. Mellichamp. But in Louisiana I have seen it 

 running up the straight trunks of trees, firmly attached to the 

 bark, without a trace of moss. In this situation, the fronds dry 

 and curl up during the hot weather, the whole plant looking 

 brown and dead; but when the spring rains come in April, the 

 curled leaves unfold, and the plant resumes growth where it 

 stopped the preceding year. 



In regard to its geographical range, I have been furnished 

 with some very interesting facts by Mr. J. H. Redfield, who has 

 followed its history closely. Inhabiting all parts of tropical 

 America and the islands of the Carribean Sea, the Polypodium 

 incanum enters the United States by the way of Mexico, through 

 Texas. The Cumberland Mountains appear to have checked its 

 direct progress, for it seems to have no desire to get up in the 

 cold; it therefore branched off, part of the little army marching 

 round to the west and north, going up the line of the Mississippi, 

 and then taking the course of the Ohio, so as to just reach that 

 state; the other winding round to the east, and then going 

 north along the Seaboard States, reaching as far as the Dismal 

 Swamp and the Natural Bridge in its northern march. In this 

 way the great ridges of mountains form an immense barrier 

 between the eastern and western colonies. 



No attempts that we know of have been made to cultivate 

 it in the open air further north, and in view of the great 

 distance from its original home, it would not probably succeed ; 

 but, fastened to blocks of wood and moss, so that it could be 

 moved to rooms, cellars, or green-houses in winter, after hanging 



