A WALKING SHIELD FERN. 



Polystichum Plaschnickianum, 



By Willard N. Clute. 



Most collectors are aware that while there is a climb- 

 ing fern family whose members all get up in the world 

 by laying hold of the stems and branches of more inde- 

 pendent neighbors, many species in other families also 

 have the same habit. In fact, in tropical regions the 

 ways ferns have of securing an advantageous position in 

 the world are apparently endless, and one is met at every 

 turn not only by climbing ferns and walking ferns, but 

 trailing ferns, creeping ferns and clambering ferns. The 

 walking ferns can boast no single family to which a ma- 

 jority of the walking species belong, though the genus 

 Camptosorus is usually dubbed the walking fern family. 

 In a moist, warm region, such as the tropics frequently 

 afford, a great variety of plants may develop the habit 

 of taking root from any part that may touch the earth, 

 and so we have walking ferns belonging to numerous 

 genera. 



One of the most interesting of these, because of its 

 resemblance in form to our own walking fern, is the 

 plant which we here call the walking shield fern (Poly- 

 stichum Plaschnickianum) . It is somewhat larger than 

 our walking fern, and far less retiring, being found 

 along the paths in open, mountainous forests, often in 

 great abundance. Like our plant, the fronds are broad- 

 est at base and taper to the summit. The fronds are nar- 

 rowed or rounded at base, but at the apex they are re- 

 tuse, that is, the tip is blunt with a slight notch in it. In 

 these notches the brown, scaly buds from which the new 

 plants grow, are situated. The plant is most abundant 

 on steep, moist banks, in which situations its fronds droop 

 until the buds at their tips are in the best position for 

 taking root. 



This plant was called Aspidium Plaschnickianum by 

 Kuntze, but the veins are free exactly as in our common 



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