DISPORUM 



DODECATHEON 



497 



D. lanuginosum, less puberulous, with Ivs. wider, more deeply 

 cordate at the base, and clasping the branches. D. Leschenaul- 

 tidnum, D. Don, differs from the others here described by hav- 

 ing white fls. India, Ceylon. B.M. 6935. D. pullum, Salisb. 

 Readily told from American forms by its brown or purplish 



green fls. India, Java, China. B.M. 916. 



W. M. 



DtSTICHLIS( Greek, two-ranked). Graminece. SALT- 

 GRASS. MARSH SPIKE-GRASS. D. spicAta, Greene, is an 

 upright, wiry grass, 10-20 in. high, with strong, exten- 

 sively creeping rootstocks. A Salt-grass found on the 

 coast of both continents, and thrives even in ground 

 heavily crusted with alkali and other salts. Prospectors 

 and miners consider its presence a sure sign of water 

 near the surface. Good grass for binding loose sands or 

 soils subject to wash. Not cult. P.B.KENNEDY. 



DISrfrLIUM:( Greek, two styles). Hamamelidacece. 

 An oriental genus of two species of evergreen trees, one 

 of which has variegated foliage, and is used for hedges 

 in China and Japan. The genus is very unlike our Witch 

 Hazel, as it has no petals, a superior ovary and 2-8 

 stamens. Lvs. alternate, thick, leathery, ovate or oblong- 

 lanceolate, entire : fls. small, polygamous. Seeds and 

 young plants of D. racemosum, Sieb. & Zucc., may be 

 obtained through dealers in Japanese plants. 



DITTANY is an old English word which in England 

 often means Dictamnus albus, a plant of the rue family. 

 The name is supposed to be derived from Mt. Dicte, in 

 Crete, where the ancient Dittany grew. The Cretan Dit- 

 tany is supposed to be Origanum Dictamnus, a plant of 

 the mint family, and of the same genus with the wild 

 marjoram. The plant commonly called Dittany in the 

 eastern U. S. is Cunila Mariana, Linn. (C. origa- 

 noides, Britton), another mint. It has been used as a 

 substitute for tea, and is a gentle aromatic stimulant. 

 All these plants yield an oil used as a mild tonic. 



DOCK. A name applied to various species of Rumex 

 (of the Polygonacece) . The commonest species grow- 

 ing in fields and yards are the Curled or Narrow-leaved 

 Dock( R. crisp^ls, Linn. ), and the Bitter or Broad-leaved 



728. 

 Spinage Dock. 



729. 

 Belleville Dock. 



Dock (R. obtusifoliiis, Linn.). These are introduced 

 from the Old World. Several species are native. 



Various species of Docks and Sorrels have long been 

 cultivated as pot-herbs. Some of them are very desir- 

 able additions to the garden because they yield a pleas- 

 ant food very early in spring, and, once planted, they 

 remain for years. The Spinage Dock and the Large 



32 



Belleville are amongst the best kinds. The former 

 (Fig. 728) is the better of the two, perhaps, and it has 

 the advantage of being a week or 10 days earlier. The 

 crisp leaves (blade 1 ft. long) appear early in April, when 

 there is nothing green to be had in the open, and they 

 can be cut continuously for a month or more. This Dock 

 is the Herb Patience (Rumex Patientia, Linn.). It has 

 long been an inhabitant of gardens, and it has sparingly 

 run wild in some parts of this country. It is a native of 

 Europe. The Belleville (Fig. 729) is also a European 

 plant, and is really a Sorrel (Rumex Acetosa, Linn.). 

 It has also become spontaneous in some of the eastern 

 portions of the country. It has thinner, lighter green 

 and longer-stalked leaves than the Spinage Dock, with 

 spear-like lobes at the base. The leaves are very sour, 

 and will probably not prove to be so generally agreeable 

 as those of the Spinage Dock ; but they are later, and 

 afford a succession. In some countries this Sorrel yields 

 oxalic acid sufficient for commercial purposes. The 

 round-leaved or true French Sorrel (Riimex scutatus, 

 Linn. ) would probably be preferable to most persons. 

 All these Docks are hardy perennials, and are very ac- 

 ceptable plants to those who are fond of early "greens." 

 Some, at least, of the cultivated Docks can be procured 

 of American seedsmen. L H B 



DOCKMACKIE. Viburnum acerifolium. 

 DODDER. See Cuscuta. 



DODECATHEON (Greek, twelve gods). Primulacece. 

 SHOOTING STAR. AMERICAN COWSLIP. Hardy herba- 

 ceous plants, with flowers that are never forgotten after 

 the first sight. Shooting Star is a capital name. The 

 flowers have been compared to a diminutive cyclamen, 

 for they are pendulous and seem to be full of motion 

 (see Fig. 730). The stamens in D. Meadia and all east- 

 ern species come to a sharp point and seem to be shoot- 

 ing ahead, while the petals stream behind like the tail 

 of a comet. The fls. represent every shade from pure 

 white, through lilac and rose, to purple, and they all have 

 a yellow circle in the middle, i. e., at the mouth of the 

 corolla. Dodecatheon is a most puzzling genus to sys- 

 tematic botanists. It is found from Maine to Texas and 

 from the Atlantic to the Pacific ; and along the Pacific 

 slope, from the islands of Lower California to those 

 of Behring straits. In this vast region, it varies 

 immensely. It is also found in Asia, especially north- 

 eastward. This wonderful distribution and variability 

 is all the more remarkable if, as Gray believed, it is 

 all one species, because monotypic genera are con- 

 sidered, as a rule, to be comparatively inflexible or 

 invariable. Dodecatheon belongs to the same order 

 with Primula and Cyclamen, but in a different tribe 

 from the latter, while its reflexed corolla lobes dis- 

 tinguish it from the 10 other genera of its own tribe. 

 For the honor of American horticulture, it is a 

 pity that the improvement of these charming Ameri- 

 can plants should have been left to English and 

 French horticulturists. An important era in their 

 amelioration was probably begun with the introduction 

 of the D. Jeffreyi from the Rocky Mts., first pictured 

 about 1866, which was stronger-growing than the com- 

 mon or Atlantic type, with longer and erect Ivs. (not 

 crowded in a flat rosette), and with larger fls. and more 

 of them. The improvement of the Shooting Stars is 

 very recent. Twenty-six horticultural varieties are given 

 in 1897 in R.H.,p. 380. The best kinds are robust in 

 habit, with 12-16 large fls., the main colors being white, 

 lilac, rose, violet, and deep purplish red, with many deli- 

 cate intermediate shades. After the fls. are gone the 

 pedicels become erect. Some species have all their 

 parts in 4's. The best picture of the most advanced 

 types is R.H. 1898: 552. For other pictures, see B.M. 12. 

 Gn. 10: 41 and 24:414. Gng.5:295. Mn.4:65. 



Of their culture, J'. B. Keller says : "All they require 

 is an open, well drained soil, not too dry, and moderately 

 rich, and a shady or partially shady position. In a sunry 

 border the fls. are of short duration. The rockery with 

 a northern or eastern aspect suits them to a dot. They 

 are prop, by division of the crowns, or by seeds, the 

 latter method being rather slow." J. W. Manning ad- 

 vises a cool spot in rich loam. The Ivs. disappear 



