76 VEGETATION OF THE PEAK DISTRICT [cH. 
Ulmus glabra 
(=U. montana) 
Sisymbrium officinalis 
Geum urbanum 
Rubus caesius 
Rosa arvensis 
Vicia sepium 
Acer campestre 
Sanicula europaea 
Caucalis Anthriscus 
Chaerophyllum temulum 
Cnicus heterophyllus 
Phragmites communis 
Arrhenatherum elatius 
(=A. avenaceum) 
Brachypodium gracile 
Arum maculatum 
Allium ursinum 
Tamus communis 
Orchis mascula 
The ash woods are much richer in species than the oak 
and birch woods, in spite of the fact that the species character- 
istic of soils containing acidic humus are abundant in the 
latter woods and absent from the former woods. Indeed, the 
floristic wealth of the ash woods is even greater than mere 
lists indicate, for several of the species which are rare and 
local in the oak and birch woods are more abundant and 
general in the ash woods. 
latter class :— 
Populus tremula 
Mercurialis perennis 
Trollius europaeus 
Aquilegia vulgaris! 
Sisymbrium officinalis 
Rubus saxatilis! 
Rosa tomentosa 
R. glauca 
R. arvensis 
Pyrus Aria! 
Geranium sylvaticum! 
Polygala vulgaris 
Tilia cordata! 
Acer campestre 
Primula vulgaris 
Myosotis sylvatica! 
Adoxa Moschatellina 
The following species belong to the 
Valeriana officinalis 
Campanula latifolia! 
Cnicus heterophyllus! 
Poa nemoralis 
Melica nutans! 
Agropyrum caninum 
Festuca sylvatica 
Hordeum europaeum! 
Carex sylvatica! 
Paris quadrifolia! 
Convallaria majalis! 
Helleborine latifolia 
(=Epipactis latifolia) 
Listera ovata 
Orchis mascula 
Habenaria virescens 
(=H. chlorantha) 
Some species which are characteristic of the ash woods of 
Yorkshire (cf. Smith and Rankin, 1903) do not occur so far 
south as Derbyshire, and apparently find the intervening 
non-caleareous soils an effectual barrier. Actaea spicata, 
1 These species are not recorded by Linton (1903) for any of the oak woods 
of Derbyshire ; but they occur in such woods on the eastern slopes of the Pennines 
a little to the north of the Peak District. 
