150 
BRITISH FERNS. 
sessile. Leaflets \ inch long, ovate, sessile, horizontal, rather 
distant, uniform. Sori abundant, heart-shaped, pale, concave, 
entire. 
Lastrea remota, Moore. 
This fern is, in its general aspect, intermediate be- 
tween Filix-mas and spinulosum., resembling the former 
in its fructification, and the latter in the divisions of 
its fronds. 
Mr. Clowes writes that he has cultivated this fern for 
several years. It was found at Windermere, about 1853, 
growing along with Filix-mas , spinulosum , and dilatatum , 
about five miles from rocks where rigidum is abundant. 
After growing it a year or two, he found that the caudex 
was not creeping, as in spinulosum ; but erect, and every 
year the plant became more and more like Filix-mas . 
In the growth of the caudex it resembles Filix-mas , but 
the loops that its young fronds make in their early de- 
velopment resemble spinulosum , as does also the form of 
its leaflets ; its pinnse are intermediate between the two, 
and it has scales, some lanceolate, like those of Filix-mas , 
some broad, like those of spinulosum , they are very nu- 
merous and closely cover the stem, which resembles 
the stalk-stem of rigidum . 
In the fernery it requires the same treatment as the 
Mountain-fern. 
CYSTOPTEMS. 
Gen. Char . Sori globular. Involucre ovate, inflated, spring- 
ing from beneath the sorus. 
23. Cystopteiis fragilis, Bernh. Brittle Bladder- 
fern. 
Caudex creeping, scaly. Stem slender, scaly at the base. 
