PRIMULA AURICULA. L.
The Yellow Auricula. Primevère Auricule. Felsen-Aurikel oder Flühblüemli.
The Marsh Orchis
(ORCHIS LATIFOLIA)
A large number of Orchids are to be found in the Alps. They form a well-defined group of plants which are particularly interesting in view of complicated devices which they have adopted to ensure the fertilisation of their seeds by the agency of insect visitors. Nearly all the English species are found in Switzerland, and most of them are met with in much greater abundance there. The beautiful pink Helleborine, the sweet-scented Butterfly Orchis, may be found in profusion on the lower mountain slopes, and the dark red Nigritella, with its odour of vanilla, and the ghost-like Coral-root, in the higher regions.
Of the genus Orchis alone there are no less than seventeen Swiss species. Many of these are much alike, and by no means easy to distinguish from one another. One of the most abundant is the Marsh Orchis, which is also met with in England, but is not nearly so common there. The plant grows in damp meadows and boggy places, where an average sized plant may be 18 inches or two feet high. Its large purple spotted flowers appear in June and may last until July.
The methods adopted by the plant to ensure the fertilisation of its flowers by means of insect visitors are most elaborate and exact, but without the aid of diagrams they are a little difficult to explain. It is curious that no honey is contained in the spur. It is probably the cell sap in it that is attractive to insects.
The Marsh Orchis will be recognised by its spreading spotted leaves, hollow stem, the palm-shaped tubers of its root, and the thick spur to the flower.
Plate XXXVI.