GTIje Crca^ttrj) at 2Sfltang. 



426 



_ DOUBLE-BEARING. Producing twice 

 in the same season. 



DOUBLY. Having a form or structure 

 repeated ; doubly-toothed = teeth them- 

 selves toothed, and so on. 



DOUCE-AME\RE. (Fr.) Solatium Dulca- 

 mara. 



DOUCETTE. (Fr.) The common Valeria- 

 nellas, which were called Valeriana locusta, 

 by Linnasus. 



DOUCIN. (Fr.) Certain varieties of Pij- 

 rus Mains. 



DOUGLASIA. A genus of primworts, 

 distinguished from its allies by the funnel- 

 shaped corolla, the tube of which is partly 

 dilated. The name was given by Dr. Lind- 

 ley as an appropriate compliment to David 

 Douglas, a well-known botanical collector, 

 to whose energy and zeal we owe the in- 

 troduction of many interesting plants. D. 

 nivalis, which is the best known species, 

 was discovered by Douglas not far from the 

 sources of the Columbia river, near snow, 

 at an elevation of 12,000 feet ; another, 

 D. arctica, was found by Sir J. Richardson, 

 on the Arctic shore between the Mackenzie 

 and Coppermine rivers. These plants have 

 forked and closely tufted stems, linear 

 leaves, and are covered with numerous 

 short stiff hairs. [G. D.] 



DOURA, or DURRA. The great Millet, 

 Sorghum vulgare. 



DOUVE, GRANDE. (Fr.) Ranunculus 

 Lingua. — , PETITE. B. Flammula. 



DOUX-GUILLAUME, — also DOUX- 

 JEAN. (Fr.) Dianthus barbatus. 



DOUZE DIEUX. (Fr.) DodecatheonMeadia. 



DOVEA. A genus of Bestiacece, consist- 

 ing of South African sedge-like plants, 

 distinguished by their simple one-celled 

 anthers, three-celled capsule opening at 

 the angles, and three (rarely two) sessile 

 stigmas. The rhizome is creeping, scaly ; 

 the stems wand-like with remote sheaths ; 

 the flowers dioecious. [J. T. S.] 



DOVE-FLOWER. Peristeria. 



DOVE'S-FOOT. Geranium dissectum. 



DOWNY. Covered with very short weak 

 close hairs. 



DRABA. Whitlow Grass. An extensive 

 genus of small annual or perennial herba- 

 ceous plants of the cruciferous order, 

 among which they are distinguished by 

 having the frond compressed, with the 

 dissepiment in the broadest diameter, and 

 numerous seeds in each cell. They are 

 most numerous in the cold mountainous 

 countries of Europe ; a few are natives of 

 America, and several of Great Britain. Of 

 these last, D. aizoides grows on walls and 

 rocks near Swansea, and is remarkable for 

 its bright yellow flowers, and glossy leaves 

 margined with hairs. It is a pretty plant, 

 well adapted for rock-work, as, indeed, are 



several of the foreign species, being of 

 humble growth, and tufted habit, and 

 made conspicuous by their white or yellow 

 flowers, which, though small, are numerous 

 and bright. Of the other British species, 

 D. verna, called also Erophila vulgaris, an 

 humble little annual with scanty foliage 

 and inconspicuous white flowers, is not 

 Avithout interest from its appearing very 

 early in the year. It grows on wall-tops 

 and dry banks. Fr. Brave ; German, Hun- 

 gerblumchen. [C. A. J.] 



DRACiENA. A genus of monocotyledons 

 of the order Liliaceo?, remarkable for the 

 elegant palm-like character assumed by 

 the greater number of the species. The 

 genus as formerly constituted was a rather 

 extensive one, but it has lately been re- 

 modelled by Dr. Planchon, who removes 

 from it all but the Draccena Draco, or 

 Dragon tree of Teneriffe ; and refers the 

 other species to Dracwnopsis, Cordyline, 

 Galodracon, Charhvoodia, and Cohnia. Thus 

 limited, Dracana is distinguished by hav- 

 ing a bell-shaped perianth deeply separated 

 into six equal segments, furnished with 

 six stamens inserted at the base of the 

 , segments, and succeeded by a fleshy berry 

 containing one, two, or rarely three seeds, 

 the ovary, which is three-celled, with a 

 single ovule in each cell, seldom perfecting 

 all of them. 



D. Draco has a tree-like stem, simple or 

 divided at the top, and often when old 

 becoming much branched, each branch ter- 

 minated by a crowded head of lanceolate 

 linear entire leaves of a glaucous green 

 colour, which leaves embrace the stem by 

 their base, and on falling off at maturity 

 leave a ring-like cicatrix or scar." The flow- 

 ers form a large terminal panicle, and are 

 individually small and of a greenisb-white 

 colour. As seen in our stoves and green- 

 houses, the plant is usually unbranched, 

 being in its ' first age ' or Infancy, which 

 lasts in its native country from twenty-five 

 to thirty years. The ' second age,' or period 

 of maturity and reproduction, and the 

 ' third age,' or period of decay, are of in- 

 definite extent. During - the former of 

 these, the scars of the leaves disappear, 

 and the thickness of the trunk is at length 

 increased by the formation of branches, 

 and the consequent deposit of new matter ; 

 while in the latter stage, aerial roots 

 appear, and glandular excrescences are 

 formed. It is only when of great age that 

 it branches. This tree derives its common 

 name from a resinous exudation known in 

 commerce as dragon's-blood. The resin has 

 j been found in the sepulchral caves of the 

 Guanches, and has hence been supposed to 

 | have been used by them in embalming 

 their dead. It appears at one time to have 

 formed a considerable branch of export 

 from the Canaries, and has never wholly 

 fallen into disuse. The colossal Dragon 

 tree at the town of Orotava in Teneriffe is 

 ! a giant amongst the plants of this type of 

 | vegetation, being according to Meyen 

 I seventy feet high, and forty-eight feet in 

 j circumference, with an antiquity which 



