ON HARDY HERBACEOUS PERENNIALS. 



269 



3ft. high, and yielding bright scarlet flowers, with yellow 

 centres, during July and August. D. grandiflortun grows 2ft. 

 high, and in July produces panicles of dark blue flowers. 

 D. midkaule is a dwarf kind, growing only i8in. high, and 

 bearing a profusion of bright orange-red flowers with yellow 

 centres ; it is an excellent rock-garden plant, and delights in 

 sunny positions. Spring-sown seedlings will flower the first 

 season. 



DiCENTRAS (DiELYTRAs) are lovely spring- or early summer- 

 flowering plants. Propagated by cuttings or by division of the 

 crowns in early spring. D. formosa has delicate fern-like 

 foliage, and umbels of drooping red flowers, produced during 

 May and June ; it grows ift. high. D. spectabilis (Bleeding 



Fig. 153. — DiELYTRA SPECTABILIS. 



Heart) (Fig. 153) is a well-known forcing plant, and also one 

 of the best for border culture; it grows 2ft. high, and flowers 

 during May, June, and July. The flowers are produced on 

 drooping racemes, and are white and rosy-crimson. 



DiCTAMNUS. — D. albus (Fraxinella) (Fig. 154) is a favourite 

 old border plant, forming a neat bush from i8in. to 3ft. 

 high. It is said that the Fraxinella has outlived father, son, and 

 grandson in the same position. It is sometimes known as the 

 "Burning Bush," because of a resinous exudation from the stems, 

 which, when a light is applied, has a luminous appearance at 



