444 



DiEDALACANTHUS 



cuspidate-aeuminate, repand-crenate : spikes as above : 

 bracts ovate-rhombio, with a slender beal^, ciliate. In- 

 serted for contrast. Probably not cult. India. 



W. H. Tapun and W. M. 



658. Decdalacanthus nervosus (X 3^). 



DXUONOBOFS (probably means God-like, of divine 

 -appearance). I'almdcece, tribe Jjepidocdrpece. Slender 

 palms, differing from Calamus in the deciduous, cymbi- 

 form or open spathes. Species about 40. Tropical 

 Asia. Same culture as Calamus. D. Draco produces 

 some of the "Dragon's Blood" of commerce. 



oalic&rpus, Mart. ( Calamus calicdrpus, Griff. ) . Stem 

 ■erect or climbing, 1 in. diam. : Ivs. 6-8 ft. long, upper 

 small with long flagella ; Ifts. very many, 12-13 in. long, 

 M-X in. wide ; petiole 1 ft., base not gibbous or puck- 

 ered. Malacca. 



Lewisiinus, Mart. (Cdlamus Zewisictnus, Griff.). 

 Stem climbing, 1 in. diam.: petiole 1 ft., base much 

 swollen, armed below with scattered, short, deflexed 

 spines, and above with straight and hooked spines 1% 

 in. long; Ifts. 13-15 in. long, %-l in. wide; sheath armed 

 with solitary or seriate flat back spines. Penang. 



Falemb&nicus, Blume. Stem erect : Ivs. pinnate, 

 broadly ovate, bright cinnamon-brown when young, and 

 Ifts. many, long, narrow ; petioles erect, with stout 

 spines on the back, which are deflexed and not thick- 

 ened at the base. Sumatra. 



perlac4nthus, Miq. Height 15 ft. Resembles D. Pa- 

 lembanicus , but the young Ivs. are nearly straw-colored, 

 and the spines are placed in irregular rings. Sumatra. 

 —A most graceful species. 



melanochaBtes, Blume. Stem erect : Ivs. pinnate, the 

 pinnae long and narrow, dark green and drooping, the 

 petioles sharp-spined at the sheathing base. Malaya. 

 —Very decorative. A small form is Var. microc&rpus. 



intermfidius, Mart. Lvs. long-petioled, 4-6 ft. long : 

 Ifts. opposite or scattered, 18-20 in. long, 1-lX in. wide, 

 linear-lanceolate, acuminate, margins and 3-5 costce 

 bristly above and below; rachis semi-cylindrical, spar 

 ringly armed ; petiole 1 ft. long, with flattened spines ; 

 stems at length 15-20 ft. long, %m. in diam. Malaya. 



plumftsus, Hort. Graceful plume-like lvs., with pinnae 

 4 ft. or less long, petioles with rigid black spines with 

 white bases. India. Jared G. Smith. 



DAFPODIE. See Narcissus. 



DAHLIA 



BAHIIA (named after Professor Andreas Dahl, a 

 Swedish pupil of Linnseus, and author of Observationes 

 Botanicae, a work of minor importance). Compdsitce. 

 Dahlias are amongst the commonest and most im- 

 portant garden plants. The spelling of the word Dahlia 

 shows that the a should be given the broad sound, but in 

 England it is everywhere given the long sound, and in 

 America it is often given the short sound. The long 

 sound of a makes the word indistinguishable from the 

 leguminous genus Dalea, named after Dale. In Germany 

 Dahlias are still commonly called Georginen, because in 

 1803 Willdenow gave the name Georgina to these plants 

 under the mistaken impression that some very different 

 plants had been previously described as Dahlia. Prac- 

 tically all of the named varieties of Dahlias have come 

 from one immensely variable species, usually known 

 as -D. variabilis. For garden purposes, however, a 

 second form of great importance, D. jtiarezii, the 

 parent of the cactus forms, must be kept distinct, 

 as will be explained later. There are 5 other species 

 cultivated to a slight extent. The genus has many 

 names of species, but most of them are synonymous 

 and ill-understood names. There are perhaps 8 or 9 

 fairly distinct species altogether, Mexican almost ex- 

 clusively, with a very few in Central and South 

 America. It is curious that these showy plants should 

 be closely related to a common weed, the beggar's tick, 

 of the genus Bidens ; but other species of Dahlia have 

 leaves whose forms pass gradually into those of Bidens. 

 Other close allies are Cosmos and Coreopsis. Cosmos 

 flowers are some shade of purple, rarely white in wild 

 nature, and only one species has yellow fls. ; Core- 

 opsis has yellow fls. only; Bidens yellow or white; and 

 none of these genera have produced double-flowered 

 forms of the first importance. Dahlia has all these col- 

 ors and more, being far richer in bright reds, and lack- 

 ing only sky blue and its closely related hues, which are 

 seen to perfection in the China Asters. Few cultivated 

 plants have such a wide range of colors as the Dahlia; 

 even the Chrysanthemum is distinctly inferior in range, 

 as it lacks the brilliant and vivid scarlet, vermilion, and 

 other shades of red. 



Although Dahlias are popular plants, especially in old 

 gardens, they are destined to still greater popularity 

 from the new " Cactus " and " Decorative " types. There 

 exists a prejudice against Dahlias in many locali- 

 ties where these new types have never been seen. This 

 prejudice is part of a reaction against formal and 

 artificial flowers in general. The old-time Dahlias were 

 as round and hard and stiff as a ball. The new-time 

 Dahlias are flatter, and tend towards loose, free, fluffy 

 chrysanthemum-like forms. The possibilities of the 

 old form have been practically exhausted ; those of the 

 new form seem to be almost as boundless as those of 

 the Chrysanthemum— which is the most fertile In new 

 forms of all the garden composites. 



Dahlia roots. 



History of the Dahlia. -Of the important and very 

 variable florists' flowers the Dahlia was one of the latest 

 to come into cultivation. The first break of considerable 

 importance in the wild type occurred about 1814. Up to 

 that time there were perhaps a dozen well-marked colors 

 in good single-flowered varieties. Dahlias had been oul- 



