148 GARDEN FLOWERS. 



half-hardy sub-shrub ; 18 inches; flowers white, in July ; south 

 of Europe ; 1640. D. tomentosum (woolly) ; hardy evergreen 

 sub-shrub ; 3 feet ; flowers red and white, in July ; south of 

 Europe ; 1817. 



DRABA. [CruciferjE.] Hardy perennials, of low growth 

 and easy culture, well suited for rock-work. Increased by 

 division. There are about forty perennial species, all dwarf, 

 mostly with white flowers. 



DRACOCEPHALUM. Dragon' s-Head. [Labiatae.] The 

 hardy perennial species of this genus are pretty border flow- 

 ers, not particular as to soil. They are propagated by di- 

 vision of the root. The hardy annual species may be sown 

 in the open border in May. 



D. Altaiense (Altaian) ; hardy perennial ; 6 inches ; flowers 

 purple, in July; Georgia; 1787. D. Argunense (Fischer's); hardy 

 perennial ; 18 inches ; flowers blue, in July ; Siberia ; 1822. D. 

 Austriacum (Austrian); hardy perennial ; I foot; flowers blue, 

 July ; Austria ; 1 547. D. canescens (hoary) ; hardy annual ; 2 

 feet; flowers blue, in July; Levant; 1711. D. grandiflorum 

 (large-flowered) ; hardy perennial ; i foot ; flowers blue, in July; 

 Siberia; 1759. D. Mexicanum (Mexican); hardy perennial ; 2 

 feet; flowers blue, in June; Mexico; 1832. D. Moldavicum 

 (Moldavian Balm) ; hardy annual ; 2 feet ; flowers blue or white, 

 in July ; Moldavia; 1596. D. peregrinum (foreign) ; hardy per- 

 ennial ; 9 inches ; flowers blue, in July ; Siberia; 1759. D.pin- 

 natum (pinnate-leaved) ; hardy perennial, prostrate ; flowers blue, 

 in June; Siberia; 1822. D. Ruyschianum (Ruysch's) ; hardy 

 perennial ; 2 feet ; flowers blue, in July ; north of Europe ; 1699. 



DRACOPIS. [Composite.] A hardy annual, allied to Rud- 

 beckia. Propagated by seeds sown in May in good garden 

 soil. 



D. amplexicaulis (stem-clasping) ; hardy annual ; 3 feet ; flow- 

 ers yellow, in July ; Louisiana ; 1793. 



DRACUNCULUS. [Araceae.] Hardy herbaceous peren- 



