FERNERIES. 



379 



are valuable for decoration in mid-winter. It grows and fructifies with 

 me in great luxuriance. 



Although the common Bracken (Pteris aquilind) grows so profusely 

 that it is probably the most common fern in the world, yet it is difficult 

 to transplant. To my mind it is exquisitely 

 beautiful, and it lives in the back part of 

 our ferneries sheltered by trees. It has, how- 

 ever, a creeping rhizome, and will travel 

 rapidly where it likes. It is difficult to 

 establish, and equally difficult to eradicate, 

 which is a disadvantage. The stems when 

 cut have a singular appearance, and abound 

 in scalariform vessels (fig. 872). 



In our outdoor ferneries for large ferns we cannot dispense with the 

 Polystichums, which are evergreen, and should be largely grown. The 

 P. aculeatuui and P. angulare are probably only varieties of the same 

 plant. The latter attains great size, and sends up fronds four feet high. 

 There are many varieties of this fern, some of which are extremely 

 beautiful. The variety of P. angulare proliferum has bulbils on the 

 axils. 



FIG. 872. Scalariform vessels 

 on Bracken. 



FIG. 873. Polystichum angulare. 



FlG. 874. -Holly Fern. 



In early spring it is interesting to observe the polystichums unfold 

 their fronds ; for whilst the lastraeas and many other ferns unfold their 

 fronds from within, those of the polystichums are unfolded from without. 

 The young frond of the polystichum (fig. 873) is a very beautiful 

 object. 



The Holly Fern (P. Lonchitis, fig. 874) is an evergreen fern of 



