FLOWERING TREES AND SHRUBS 87 



H. pilostjm. — South of France, 1881. This bears white 

 flowers that are of good substance, and about an inch 

 across. 



H. pomfolium (syn H. pufoendentim). — Europe (Britain) 

 and North Africa. This is a neat-growing shrub, of very 

 dwarf growth, with hairy leaves and yellow flowers; and 

 H. polifolium roseum has pretty rosy-red flowers. 



H. umbellatum. — South Europe, 1731. A neat, small- 

 growing species, with white flowers and glossy-green leaves 

 covered with a rusty-white tomentum beneath. 



H. vulgare. — Common Rock Rose. Europe (Britain), 

 North Africa, and West Asia. A widely-distributed native 

 plant, of dwarf growth, with linear-oblong, hairy leaves, 

 and usually yellow flowers. H. vulgare nummularium 

 differs in having the leaves green and sub-orbicular, with 

 yellow flowers. H. vulgare barbatum is of erect habit, 

 with silky, hairy, oval leaves. H. vulgare mutabile bears 

 pale-rose flowers, marked with yellow at the base. H. 

 vulgare grandiflorum is remarkable for the large, bright- 

 yellow flowers, and is one of the most beautiful and worthy 

 varieties. H. vulgare ovalifolium (syn H. serpyllifolivm) 

 bears yellow flowers and ovate leaves, with the margins 

 revolute. H. vulgare hyssopifolium bears reddish flowers, 

 but the colouring varies considerably, and saffron is not 

 uncommon. 



The Rockroses are very valuable shrubs, in that they 

 will succeed on poor, gravelly banks where few other 

 plants could eke out an existence. They cannot withstand 

 stiff soil, nor that at all inclined to be damp, their favourite 

 resorts being exposed, rocky ground, and dry, gravelly 

 banks. Being readily increased from cuttings, which take 

 root well under a hand glass or in a cool house, it is 

 advisable, at least with the more tender forms, to have 

 at hand a stock, so that blanks in the shrubbery may be 

 filled up. 



