268 
THE FERN WORLD 
under, giving a concave appearance to the back of each lobe. 
The whole frond, indeed, has a curious general resemblance 
to a Bracken frond in miniature. One feature which further 
helps to make this species distinct from Dry op ter is (though 
some botanists merely regard it as a variety of the latter), 
must be noticed. There is not, as in D ryopteri.s, the curious 
appearance of three little green balls when the pinnae are 
unrolling, for each pinna separately unfolds. The rhizoma 
creeps extensively, and is provided with abundant fibrous 
rootlets. There are no variations from the normal form of 
Calcareum. 
Distribution. — In Europe the range of this Fern extends 
to France, Germany, Hungary, Norway, and Switzerland. 
The species inhabits also the Himalayan Mountains, the 
United States of America, and Canada. In England it is 
found in the counties of Cumberland, Derby, Durham, 
Gloucester, Hereford, Lancaster, Oxford, Somerset, Stafford, 
Westmoreland, Wilts, Worcester, and York. Iu A Vales it 
occurs in the counties of Brecknock, Carnarvon, Denbigh, 
and Glamorgan. In Scotland it is extremely rare. From 
Ireland it is altogether absent. 
Culture. — Wherever cultivated, whether on the open 
rockery, in pots, in cases, or in the Fern house, it is always 
beneficial to place amongst the soil — which should con- 
sist of leaf-mould, and sand and loam in equal quantities 
— little blocks of limestone, the caudices of the Fern 
being placed between the blocks of stone. We have 
seen that this Fern does not require the deep shelter 
which Dryopteris demands ; but if well shaded in a nook at 
the foot of the rockery, it will become more grandly de- 
veloped than if exposed in sunny places. It is a very hardy 
species, may be readily multiplied by a division of its 
branching rhizomas, and will creep extensively wherever 
planted. 
