POLYPODIUM. 
117 
compost of fibry peat, leaf-mould, and silver-sand. The 
plant is well worth the trouble of such treatment, its 
form and tint being alike acceptable in the ornamental 
bouquet and in the drawing-room vase. 
This fern is found among the Swiss Alps, in North 
America, Canada, and even Iceland and Siberia. 
4. Polypodium Bryopteiis, Linn. Tender Three- 
branched Polypody, or Oak-fern. 
Sori in two rows, near the margin of the leaflets. Caudex 
long, slender, widely creeping. Stem long, thin, and scaly. 
Fronds 3-branched, twice pinnate, and of thin texture. 
The name Dryopteris is derived from drys, the Greek 
for oak, and pteris , fern. There is as little significance 
in the name as in that of the 
last species, except that the 
spreading branches may bear 
some resemblance to those of 
the tree in question. 
The caudex is slender, brittle, 
and creeps to a great distance, 
often extending its ramifica- 
tions over half an acre of 
ground ; the stem is thrown 
up in May, and resembles a 
slender wire, crowned with a 
tiny verdant ball. It soon be- 
comes tinged with purple or 
brown. Brown scales accom- 
pany both the young shoots of 
the caudex and the base of the slender stem. The leafy 
part of the frond is about two-thirds the length of the 
