ROSACEA 137 



Dryas L. 

 Dryas ociopetala L. 



Stem somewhat shrubby and woody, branched, prostrate, 

 forming flat cushions, extending sometimes a couple or more feet 

 from one root. Leaves evergreen, cordate-ovate, crenate, blunt, 

 glabrous and shining on the upper surface, white and hoary beneath. 

 Stipules lanceolate-subulate, more or less hairy like the leaf-stalk 

 and flower-stalk. Calyx and upper part of flower-stalk with short, 

 glandular hairs. Flowers solitary, large, white, terminal. Seed- 

 vessel feathery in fruit. Petals 8-9. Calyx 8-9 lobed. 



Rocky places and high pastures, especially on limestone, from 

 4300 to 9000 feet, and occasionally descending to the plains ; 

 frequent. June to August. 



Distribution. — Mountain ranges of Europe from the Pyrenees to 

 the Caucasus, Arctic Europ^, Siberia, N. America ; Scotland. 



There are only 2, or possibly 3, species of this genus ; the present 

 one is found fossiUzed in parts of Europe. 



RuBUS L. 



Except for the Wild Raspberry {Rubus idaus), and the Stone 

 Bramble {R. saxatilis) very few of this large genus are ever seen 

 in the sub-alpine region of Switzerland. 



Rubus saxatilis L. Stone Bramble. 



Rootstock woody but slender, with a few creeping runners 

 rooting at the nodes, and erect or ascending simple stems, 5-10 

 inches high, slender and either unarmed or with a few small prickles. 

 Stipules lanceolate. Leaflets usually 3, pale green and thin in 

 texture. Flowers on slender pedicels, 2-3 in the axils of the upper 

 leaves, forming very short racemes. Petals very narrow, dirty 

 white or greenish yellow. Fruit red, shining, with only 2 or 3 

 large drupes. 



Open woods and steep mountain sides. Flowers in June ; fruit 

 in August. 



Distribution. — Spread over the mountain regions of Europe, 

 Central and Northern Asia, and descending to lower elevations 

 in more northern latitudes. British. 



Rosa L. 



This well-known and well-marked genus is widely diffused over 

 the northern hemisphere, in the new world as well as the old. 



In the sub-alpine region of Switzerland and the Jura, the chief 

 species are the following : 



R. alpina L., R. fomifera Herrm. (with very large fruits) ; R. 

 spinosissima L. (fairly common in the Jura) ; R. iomentosa Lin., 



