POLYPODIUM PILOSELLOIDES. 



By Willard N. Clute 



When we speak of the common polypody we seldom 

 stop to think that this name can be applied to our familiar 

 species in but a comparatively small part of the world. 

 It is true that this species, or forms that closely resemble 

 it, is widely distributed, but in many localities it is any- 

 thing but common and from others it is absent entirely. 

 So great is the Polypodium genus, however, that there 

 is usually a common polypody for every clime though the 

 species may vary with the latitude, longitude or altitude. 



One of the common polypodies of the West Indies is 

 the little Polypodium pilosellaides illustrated herewith. 

 From sea-level to altitudes of a mile or more it is likely 

 to be a familiar feature of the wayside growing" on rocks, 

 earth, old logs and living trees. Like our little gray 

 polypody of the South, which inhabits similar situations, 

 it seems to prefer the trunks of trees up which it climbs 

 for long distances by means of its slender cord-like root- 

 stocks. In the forests it often gets well up into the tree- 

 tops. The thick and dark green fronds are usually not 

 as long as one's finger and are entire with an ovate, oblong 

 or lanceolate outline quite unlike the polypodies of north- 

 ern regions though similar to many allied species in the 

 tropics. They are scattered along the freely branching 

 rootstock on short stipes and at first glance the plant 

 might be mistaken for some flowering vine. 



As in many other ferns, the work of spore-bearing has 

 produced a reduction of leaf surface that causes a marked 

 difference between the fertile and sterile fronds. The 

 whole plant is scaly. Upon the fronds are many shield- 

 shaped scales and the rootstock which appears as thick 

 as cord is found to be scarcely heavier than strong thread 

 when the scales that clothe it are removed. 



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