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BRITISH FERNS. 
the apex ; the stems are covered with whitish scales. A 
native of Jamaica. 
Cy at he a medullar is. Pithy Cyathea. Still more stately ; 
the caudex like the bole of a tree ; the fronds 14 or 1 5 
feet long ; the stems purplish. It grows rapidly, and is 
a very desirable fern where there is plenty of room. Its 
home is in the valleys of New Zealand. 
Cyathea patens. Spreading Cyathea . Caudex slender, 
3 or 4 feet high ; fronds 6 to 8 feet long, tripinnate, 
yellowish-green ; the stems light brown and scaly. Like 
the Cyathea elegans, it is a native of J amaica. 
Ceratopteris is a genus of aquatic ferns ; the name is 
derived from two words, keras, a horn, and pteris, a fern, 
and relates to the horn-like form of the segments on the 
fertile fronds. 
Ceratopteris thalictroides . This is a water-plant grow- 
ing in stagnant pools in tropical America and Asia. 
The fertile fronds are erect, three or four times pinnate ; 
the segments linear, contracted, and horn-like ; the 
barren fronds are tripinnate, but the segments are ob- 
long. In cultivation this fern should be placed in large 
pots, and plunged in a cistern. It is an annual, but 
little knobs or bulbs grow in the hollows between the 
segments of the frond, which easily root themselves, 
and the spores germinate readily also. 
Hymenophyllum cruentum. Crimson Filmy - fern . 
Fronds simple, lanceolate, broad at the base, and nar- 
rowing to the apex, crenate at the margin, 6 inches long; 
the sori are borne on the margin, forming a fringe round 
it. Of a beautiful rose or blood-colour. This lovely 
species is peculiar to Chiloe. 
Lygodium is a generic name derived from lygodes , 
flexible , and refers to the climbing habit of the group. 
