POLYPODIUM. 75 



known from the otlier British Polypodies. The veins in 

 the lobes of the pinnse are pinnate ; that is to say, there 

 is a slender midvein, from which alternate venules, mostly 

 unbranched, extend to the margin ; those near the base of 

 the lobes bearing each one small circular sorus near 

 their extremity — the fructification thus becoming almost 

 marginal. 



It is a very delicate and graceful Fern for pot-culture or 

 for a Wardian case, and requires plenty of percolating 

 moisture. On the damp, shady sides of sheltered arti- 

 ficial rockwork, in the open air, it grows with tolerable 

 vigour. 



PolysticJmm Phegopteris, Lastrea Pliegopteris, Gymno- 

 carpium Phegopteris, Phegopteris poly podioides, and Phe- 

 gopteris vulgaris, are names which have been proposed for 

 the Beech Fern. 



Polypodium Dryopteris, Linnceus. 



The Smooth Three-branched Polypody, or Oah Fern,. 

 (Plate II. fig. I.) 



This is at once known among the Polypodies by having 

 its fronds smooth and divided into three branches ; when 

 the fronds are but partially developed, this latter charac- 



