154 VEGETATION OF THE PEAK DISTRICT [cH. 
Rumex conglomeratus 1 | Mentha spp. la 
Polygonum Hydropiper o | *Mimulus Langsdorfii 1 
Ranunculus repens a | Veronica Beccabunga o toa 
Nasturtium palustre r | Gnaphalium uliginosum ) 
N. officinale la | Petasites ovatus a 
Barbarea vulgaris o | Pulicaria dysenterica 29 
Potentilla Anserina a | Alopecurus geniculatus ) 
Apium nodiflorum r || Carex hirta 1 
Sium erectum r Juncus bufonius la 
Scutellaria galericulata ) 
REED SWAMPS 
There being no extensive, shallow, sheets of water in the 
district, it follows that reed swamps are not common and are 
not typically developed. The most characteristic member 
(Phragmites communis) of reed-swamps in general has only, 
in the course of the present botanical survey, been observed in 
lower Monsal Dale, where, in the back waters of the river Wye, 
it forms one or two small associations or societies. However, 
most of the streams of this hilly district have a fairly strong 
current; and this factor of itself is sufficient to account for the 
paucity of reed swamps of Phragmites communis by the stream 
sides. It appears to be generally the case that this plant 
only forms typical reed swamps in stagnant or almost stagnant 
waters; and, where the water is well aérated, any reed swamps 
that occur are dominated by other plants, such as Glycerma 
aquatica and Phalaris arundinacea. In this district the two 
latter plants are frequently dominant in plant societies or 
small associations up to about 600 feet (183 m.). The latter 
plant, however, occasionally occurs up to about 900 feet (274 m.). 
The following plants occur in the smail and rather non- 
typical reed swamps of the southern Pennines: it will be seen 
that many of the species are in this district only of local 
occurrence :— 
