This section is from the book "British Wild Flowers - In Their Natural Haunts Vol2-4", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
Remains of this rare but interesting plant are found in Late Glacial beds in Edinburgh and Perth. It is found in the Arctic and Alpine regions of the North Temperate and Arctic Zones. In Great Britain it occurs in Stafford, Carnarvon, York (Mid, W., and N.W.), Westmorland, Mid and East Perth, Forfar, South Aberdeen, Easterness, Argyle, Cantire, North Ebudes, West Ross, Sutherland, Orkney, that is from Carnarvon and Stafford to Orkney, ascending to 2700 ft. and descending to the sea-level in N. and W. Ireland.
The Oak-leaved Mountain Avens is a local plant, which is restricted in England and Scotland to the mountain ridges of the Pennine and Highland groups, where it grows on rocky heights, mainly limestone rocks. The Gentians, Saxifrages, and other rare alpine and subalpine species are found in the same spots.
This rare alpine flower, like many others that adorn the hills, is dwarf but delicate and has a large and beautiful flower. From the resemblance of the leaves to those of the Oak, on a small scale, Linnaeus gave it the first Latin name. The leaves are stalked, oblong, toothed irregularly near the base of the stem, and woolly.
The flowers are large, with white petals, and, as indicated by the second Latin name, these are eight in number. The sepals are long, and covered with black, glandular hairs, like the scapes, which are also hairy and glandular.
This choice little plant is never more than 9 in. in height. It is in flower in June, July, and August. It is a perennial and propagated by division. One may find it in many rock-beds in the garden.
The Mountain Avens is androdioecious. The hermaphrodite flowers are usually feebly proterogynous like Avens, the stigmas maturing first. The stigmas rise when the flower opens, are sometimes covered over by the inner stamens even for some time after the outer anthers have opened,1 and these flowers are proteran-drous, the anthers ripening first. The flowers are large and contain honey, which is concealed.
Long hairs are developed on the fruit as a feathery down to aid in dispersal by the wind. The carpels are numerous.
This handsome species is a rock plant, being found only on limestone rocks, and is therefore a lime-loving plant.
A moth, Grapholitha com-plana, is the only insect which infests it.
Dryas, Linnaeus, is from the Greek, drus, oak, to which its leaves have a resemblance. The second Latin name refers to a characteristic of the flower, which has 8 petals.
The plant is called Mountain Avens and Wild Betony.
Essential Specific Characters:96. Dryas octopetala, L. - Stem decumbent, woody, leaves stalked, downy white below, oblong, crenate, flowers white, petals 8, sepals equal 8, achenes with feathery awn.
Photo. Dr. Somerville Hastings - Oak-leaved Mountain Avens (Dryas Octopetala, L.)
1 The outer open first, and insect visitors touch the stigmas and anthers on either side, and establish crossing. When no visitors occur the styles bend outwards and touch the inner anthers, and self-pollination occurs from this cause and the later pendent position of the flower.