126 
HISTORY OF BRITISH FERNS. 
seldom exceed two or three feet in height ; they are erect, 
and their form is narrow-lanceolate ; the pinnae are taper- 
pointed ; the pinnules set quite clear of each other, very 
narrow, that is, linear, with sharp points, the margins 
bluntly toothed, but rolled under so that very little of the 
toothing is seen ; the sori are very often confluent. It 
occurs in boggy places. 
The variety latifolium, found a few years since in West- 
moreland, is another very distinct and a strong-growing 
form. It differs from the common sort, in the elongate 
or oblong-lanceolate outline of its fronds, and in the broad, 
leafy, crowded development of its ovate irregularly-lobed 
pinnules, which are deeply toothed at the margin, with the 
curved sori lying near the sinus of the lobes. 
The form called moUe, which is perhaps only one of the 
smaller states of the common plant, has ovate-lanceolate 
fronds growing nearly erect, the lower pair of pinnae being 
short and deflexed ; it has flat toothed pinnules, connected 
at their base by a slender wing to the midrib, and produces 
its sori distinct. This is a small form, often not more 
than about a foot in height. 
The variety marinum, a very curious and distinct-look- 
ing plant, found by Dr. Dickie in a sea-cave at Aberdeen, 
