Lastrea Oreopteris, Presl. 
Lastrea Montana, Newman . 
MOUNTAIN FERN. 
Root — Radicles strong, tough, and penetrating ; caudex 
thick, tufted, and scaly. 
Frond — Elongate-lanceolate pinnate; the seven lower 
pairs of pinnae becoming gradually more narrow, the lower- 
most even in full-grown specimens being little more than 
half an inch long; fronds from one to three feet in length. 
Stipes — Short (about one -seventh the length of the 
frond), moderately covered with light brown scales. 
Pinnae — Linear-lanceolate, deeply pinnatifid, opposite, 
acute at the apex. 
Pinnules — Pinnules rounded, and slightly crenate. 
Venation — Lateral veins alternate; the mid vein termi- 
nates with a fork; the two veins next the extremity are 
simple, the remainder are forked. 
Fructification — Clusters of capsules circular, near the 
extremity of each branched or simple fork, giving to the 
pinnule the appearance of a marginal braiding. 
Habitat — In mountainous districts, generally in moist 
situations. Plentiful in the High Peak ; found also on the 
sandstone formation in the neighbourhood of Matlock and 
Ashbourne. 
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