44 BOTANY. 
buildings. Some of these seem to select the habitations of man and animals, 
on account of certain nitrogenous and inorganic matters which enter into 
their composition. Among them may be noticed Nettles, Pellitory, Docks, 
Borage, Henbane, Xanthium. Here also have been placed some plants 
immediately connected with the habitation of man, such as Racodium cellare, 
a fungus found on wine casks; Conferva fenestralis, an alga produced on 
window-panes; and Conferva dendrita, one developed on paper. Some 
plants, as Sempervium tectorum, select the roofs of houses. _ 
11. Plants growing in Vegetable Mould, such as bog plants, or those 
growing on wet soil, so soft that it yields to the foot, but rises again; and 
marsh plants, growing in wet soil, which sinks under the foot and does not 
rise. ‘To the former class belong such plants as Pinguicula alpina and 
Primula farinosa ; to the latter, such as Menyanthes, Comarum, Bidens 
cernua. 7 
12. Forest Plants, cluding trees which live in society, as the Oak, the 
Beech, Firs, &c., and the plants which grow under their shelter, as the 
greater part of the European Orchises, some species of Carex and Orobanche. 
Some plants especially grow,in pine and fir-woods, as Linnea borealis and 
some Pyrolas. 
13. Plants of Sterile Places, found in barren rocks, by road-sides. This 
is a heterogeneous class, and contains many plants of uncertain character. 
Under it are included the plants of uncultivated grounds, as those found on 
moors, where Calluna vulgaris, common heath, and various Heaths, Juniper, 
Andromeda, and some species of Polytrichum occur. 
14. Plants of the thickets or hedges, comprehending the small shrubs 
which constitute the hedge or thicket, as the Hawthorn and Sweet-brier ; 
and the herbaceous plants which grow at the foot of these shrubs, as Adoza, 
Wood Sorrel, Violets ; and those which climb among their numerous branches, 
as Bryony, Black Bryony, Honeysuckle, Traveller’s Joy, and some species of 
Lathyrus. | 
15. Plants of the Mountains, which De Candolle proposes to divide into 
two sections: 1. Those which grow on Alpine mountains, the summits of 
which are covered with perpetual snow, and where, during the heat of summer, 
there is a continual and abundant flow of moisture, as numerous Saxi- 
frages, Gentians, Primroses, and Rhododendrons. 2. Those inhabiting moun- 
tains on which the snow disappears during summer, as several species 
of Snap-dragon, among others the Alpine Snap-dragon. Umbelliferous 
plants, chiefly belonging to the genus Sesseli, meadow Saxifrage, Labiate 
plants, &c. 
C. Prants Growine IN SpeciaL Locatirizs. 
16. Parasitic Plants, which derive their nourishment from other vegeta- 
bles, and which, consequently, may be found in all the preceding situations ; as 
the Mistletoe, species of Orobanche, Cuscuta (Dodder), Loranthus, Rafflesia, 
and numerous Fungi. 
17. Pseudo-parasitic Plants, or Epiphytes, which live upon dead 
44 
