1870.] HARDY HERBACEOUS PLANTS. 311 



A. alpina, Alpine Rock-Cress.- — This form does not differ much from 

 A. albida, except in respect of freeness of growth, in which it is inferior 

 to that species, and in the smaller size and closer toothing of the 

 leaves. The flowers are equally profuse and white, and appear from 

 March till June, but are less disposed to flower either before or after 

 those periods. Enjoys a very wide distribution on the Alps, and 

 affects a variety of habitats, but chiefly stony places. 



A. blepharojphylla, Califomian Rock-Cress. — This species is of recent 

 introduction. It is nearly allied to A. albida, having the same mode 

 of growth and similar character of foliage, but the flowers, also of the 

 Albida type, are of a rosy-purple colour. The flowers appear in May 

 and June. Best adapted for culture on rockwork, but in dry warm 

 soils will likely prove hardy in most parts of the country in the open 

 border. Height about 9 inches. Native of California. 



A. lucida, Shining Rock-Cress. — The species in this case is of much 

 less ornamental value than the variety named A. lucida variegata, 

 which is undoubtedly one of the handsomest of hardy yellow variegated 

 plants at present in cultivation. The plant grows in close tufted 

 habit, producing close rosettes of shining dark-green leaves beautifully 

 margined with bright yellow. About 4 to 6 inches high, not plentiful 

 in the country ; the flowers are white, but should not be allowed to 

 appear in the variety, as the foliage becomes injured thereby. The 

 normal form is a pretty plant on rockwork, being very neat and com- 

 pact in growth. Native of Hungary. 



A. procurrens, Procurrent Rock-Cress. — This is a pretty smooth- 

 growing prostrate plant, with entire, shining, almost linear leaves, entire 

 on the margins. Flowers largeish, pure white, rather profuse, appear- 

 ing in April, May, and June ; height 6 to 9 inches. I have grown this 

 plant for greenhouse decoration in shallow well -drained pots, and 

 found it most useful in the end of February and throughout March for 

 ornamenting front stages. A very pretty variety with variegated 

 leaves is not very plentiful in gardens, but it is a beautiful plant, and 

 should be more popular once it is more widely known than it is at 

 present. Native of Carniola and Hungary. Easily propagated by 

 cuttings in early summer, and by division in autumn or winter. 



Aubrietia. — A very interesting and attractive genus, of few species 

 so called, but which are not strikingly distinct in character one from 

 the other. They are all, however, worthy of cultivation, though not 

 together in one collection, except perhaps in the largest; but no collec- 

 tion of spring flowers may be considered complete without one or 

 other of their best forms in its ranks. The same spreading trailing 

 manner of growth, and the same rosette style or crowding of the 

 leaves at the extremities of the stems and branches, as characterise the 



