10 
LASTREA OREOPTERIS. 
The ■word Lastrea was given in honour of M. de 
Lastre, a distinguished French Botanist. 
THE HEATH SHIELD FEKN, OK SWEET MOUNTAIN EEKN. 
Syn. — j Polypodium montanum, P. oreopteris, P . fra- 
grans, Aspidium odoriferum, A. oreopteris, fyc. 
The fronds are vesica shaped, tapering upwards and 
downwards to a point each way, for the lower pinnse 
diminish almost to nothing, and are set wide apart. 
They spring from the caudex or stump of the root 
in a circle, and dispose themselves like the feathers 
of a shuttlecock, generally attaining the height of 
from two to three feet. The stalk has a few scales 
on it below, but is hairy above, and is indented 
longitudinally by a channel on its upper side. The 
pinnse are sometimes set opposite each other. They 
are pinnatifid, or cleft nearly to the rachis, to form 
the pinnules, which last are blunt, flat, and entire. 
The sori are arranged round the margin of each 
pinna, like a beautiful trimming of little brown 
beads. When they are in full show the effect is 
very striking. This fern has been mistaken for the 
Lastrea jilix-mas, but it differs in being more deli- 
cate, smaller, and smoother : its pinnules differ also 
in not being crenate or notched, as in the Male fern. 
But the disposition of the sori settles every doubt in 
an instant. In the male fern they are ranged in a 
line at some little distance on each side of the mid- 
vein, and are confined to the lower half of the pin- 
nule ; whilst in the one under consideration they are 
smaller, set closer together, and are disposed round 
the edge even to the apex. And the fragrance is so 
strong and so grateful as at once to distinguish it 
from all others. A number of small, yellow, shining 
glands will be seen on examination on the under 
side. On being handled these give out a very agree- 
able balsamic odour. As to the venation, each lobe 
is traversed by a wavy mid-vein, which gives off 
alternate lateral ones to the sori at the margin. 
Uses. — 
Where found.— I t is by no means common near 
