Watson further brought out the striking fact that the west and east of Britain each had species peculiar to it; the former he characterized as Atlantic, the latter as Germanic. The Cornish heath (Erica vagans) and the maiden-hair fern (Adiantum CapillusVeneris) may serve as instances of the one, the man-orchis (Aceras anthropophora) and Reseda lutea of the other.
The word Orchis is used in a special sense to denote a particular genus of the Orchid family (Orchidaceae); very frequently, also, it is employed in a more general way to indicate any member of that large and very interesting group. It will be convenient here to use the word Orchis as applying to that particular genus which gives its name to the order or family, and to employ the term "orchid" in the less precise sense.
In the common orchids of British meadows, Orchis Mori-o, mascula (Shakespeare's long purples), &c., the general structure of the flower is as we have described it (figs.
Such being in general terms the mechanism of the flower of a common orchis, let us now see how it acts.
This fact will account for the profusion with which some orchids, like the common bee orchis for instance, are found in some seasons and their scarcity in others.
- Tubercular roots of Orchis mascula, a terrestrial Orchid.
The most important are the following: Ophrydineae, with about 45 genera, of terrestrial orchids, mainly north temperate, including the British genera Orchis, Aceras, Ophrys, Herminium, Gymnadenia and Habenaria.
The order is well represented in Britain by 18 genera, which include several species of Orchis: Gymnadenia (fragrant orchis), Habenaria (butterfly and frog orchis), Aceras (man orchis), Hermin- ium (musk orchis), Ophrys (bee, spider and fly orchis), Epipactis (Helleborine), Cephalanthera, Neottia (bird's-nest orchis), one of the few saprophytic genera, which have no green leaves, but derive their nourishment from decaying organic matter in the soil, Listens (Tway blade), Spiranthes (lady's tresses), Malaxis (bog-orchis), Liparis (fen-orchis), Corallorhiza (coral root), also a saprophyte, and Cypripedium (lady's slipper), represented by a single species now very rare in limestone districts in the north of England.
Orchis papilionacea, L.
Geranium, Cardamine pratensis, mallows, Rubus, Oxalis, Epilobium, &c., but many species show more or less well-marked median symmetry (zygomorphism) as Euphrasia, Orchis, thyme, &c., and red, blue and violet are the usual colours.
The following, however, among others, are distributed throughout the whole, or a great part, of the range: Colchicum alpinum, Crocus vernus, Orchis globosa, Petrocallis pyrenaica, Astragalus depressus, A.
Thyme and the small white dune-rose (Rosa pimpinellifolia) also grow in the dunes, and wall-pepper (Sedum acre), field fever-wort, reindeer moss, common asparagus, sheep's fescue grass, the pretty Solomon-seal (Polygonatum officinale), and the broadleaved or marsh orchis (Orchis latifolia).
An orchis found in the mountain yields the dried tuber which affords the nutritious mucilage called salep; a good deal of this goes to India.