ALPHABETICAL LIST OF PLANTS 273 



D. cuspidata. — Very small tufts of dark green ciliated leaves, and 

 yellow flowers, in March. Increased by seed. 



D. grandiflora. — The largest-growing of the genus, with white 

 flowers. 



Other varieties, all of very diminutive growth, are — D. brunicpfolia^ 

 ciliarzs, Kotschyi, Olpnpica^ and rigida^ all bearing yellow ^ 

 flowers. Those with white flowers are — D. bryoides, Mawii^ nivalis^ 

 and salamoni. 



Dracocephalum (Labiatae), Dragon's Head 



This genus, though generally considered herbaceous plants, give a 

 few varieties suitable for the rock garden. They can all be 

 increased by seed or division. 



D. grandiflorum (syn. D. altaicense). — Requires very well- 

 drained, sandy loam. Of rather compact, shrubby habit, growing 

 only about 8 to 12 inches high. Narrow, greyish leaves, and 

 handsome blue flowers, in early summer, in whorled spikes not 

 very easy to grow in any but a dry climate. Young plants should 

 be protected from the attacks of slugs. Increased by division. 



D. RuyscMana.— Light sandy soil, well drained, on elevated 

 spots. Spreading, rather prostrate habit, of fairly rapid gro^^i:h. 

 Rosy-purple flowers, freely produced in late summer. Increased 

 by seed or division. Japonica is a deeper and better-coloured 

 form of this, and altogether a finer plant. 



Other suitable varieties, all requiring the same conditions as to 

 soil and position, are — 



D. austriacu7n. — Large blue flowers, in whorled spikes. 



D. botrioides. — Purple flowers in June. 



D. speciosum. — Grows about 18 mches high, with pink and blue 

 flowers, in July. 



Drosera (Droseraceae), Sundew 



Interesting little sundews for the bog garden, growing them in 

 wet sphagnum moss. Besides our native kinds, D. intermedia^ 

 D. longifolia^ and D. obovate^ we should try the North American 

 sundew, D. filiformis^ with its rose-purple-coloured flowers, and 

 glandular, hairy leaves. It is quite hardy, but difficult to cultivate 

 even in wet sphagnum moss. 



Dry AS (Rosaceae) 



A small genus of woody, spreading plants of much beauty and 

 value. 



D. octopetala (syn. D. integrifolid). — Mountain Avens. Sunny 

 slopes, peaty loam, well drained, yet rather moist. Likes limestone. 



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