1004 



DICKSONIA 



DICTYOSPERMA 



should be gradually decreased until winter, when the 

 trunks should be kept merely moist all the time. Only 

 in the hottest summer days is slight shade needed. It is 

 a pity to grow tree ferns in pots, but if this must be 

 done several principles should be observed. The lapse 

 of a single day's watering will often cause serious 

 damage. As a rule, the pots should be of the smallest 

 size consistent with the size of the trunk. Three or 

 4 inches of soil all around the trunks are enough. The 

 above points are taken from Schneider's "Book of 

 Choice Ferns;" see also the discussion of tree ferns, 

 under Ferns, Vol. III. 



antarctica, Labill. Lf.-stalks short, the scales dense, 

 dark purplish brown; Ivs. 5-6 ft. long, the middle 

 pinnae 12-18 in. long; segms. oblong, the sterile incised. 

 Austral, and Tasmania. G.C. III. 9:81. Trunk some- 

 times 30-35 ft. high. A very useful decorative plant. 



squarrdsa, Swartz. Lf.-stalks short, the scales hair- 

 like, light colored: Ivs. 3-4 ft. long, the pinnae 9-15 in. 

 long; segms. lanceolate, the sterile toothed, the ribs 

 scabrous. New Zeal, and Chatham Isl. 



L. M. UNDERWOOD and WILHELM MILLER. 



DICLfPTERA (named in allusion to the 2-celled 

 winged caps.). Acanthacese. Pubescent or hirsute 

 annual or perennial herbs or sub-shrubs, with red, 

 violet or blue bracted flowers in terminal or axillary 

 clusters, in the tropical parts of the world, 1 or 2 of 

 which may sometimes occur in the trade. Lvs. opposite, 

 entire, the plant usually evergreen: corolla-tube, 

 slender, often somewhat expanded above; limb 2- 

 lipped, the lips narrow; stamens 2, on the throat. D. 

 Niederleiniana, Lind., has been recently intro. abroad 

 from Argentina: sub-shrub: Ivs. oval, to 3 in. long, 

 petioled, rounded at apex, densely pubescent: fls. 

 about 1 % in. long, several crowded in a terminal pani- 

 culate cyme. D. Tweediana, Nees, of Uruguay, is a 

 showy perennial with orange-red fls. and oblong-obtuse 

 Ivs. There are probably 75 species of Dicliptera. Very 

 likely the horticultural names are confused as between 

 this genus and others. L. jj. B. 



DICLYTRA: An ancient typographical error for Dielytra. See 



Dicentra. 



DICTAMNUS (old Greek name, supposed to indicate 

 foliage like the ash : hence Fraxinella, diminutive of the 

 Latin Fraxinus, an ash). Rutacese. GAS-PLANT. BURN- 

 ING-BUSH. FRAXINELLA. DITTANY. A hardy peren- 

 nial herb. 



Stout plants woody at the base: Ivs. alternate, odd- 

 pinnate, the Ifts. ovate, serrulate and pellucid-punctate: 

 fls. showy, white or rose, on bracted pedicels; petals 5, 

 the lower one declined; disk thickish, annular; stamens 

 10, declined; ovary deeply 5-lobed, 5-celled, hispid, 

 becoming a hard 5-divided caps., each division or 

 separate part being 2-3-seeded. One variable species, 

 native from S. Eu. to N. China. 



This genus includes an old garden favorite which has 

 a strong smell of lemon, and which will give a flash of 

 light on sultry still summer evenings when a lighted 

 match is held under the flower-cluster and near the main 

 stem. It is one of the most permanent and beautiful 

 features of the hardy herbaceous border. Instances are 

 known in which it has outlived father, son and grand- 

 son in the same spot. It thrives in the sun. 



The gas plant makes a sturdy, bold, upright growth, 

 and a clump 3 feet high and as much in thickness makes 

 a brave sight when in flower. A strong, rather heavy 

 soil, moderately rich, is best for these plants They are 

 not fastidious as to situation, succeeding as well in par- 

 tial shade as when fully exposed to the sun, and drought 

 will not affect them when once fairly established. Old 

 strong clumps are good subjects as isolated specimens 

 on a lawn, and a large patch, planted in the border, is 

 not only effective while in full flower, but the dark, 



persistent foliage is ornamental throughout the sea- 

 son. It is not advisable to disturb the plants very often, 

 as they improve with age, producing taller flower-stems 

 and more of them as they grow older. They are excel- 

 lent for cutting, especially the white variety. Propaga- 

 tion is accomplished with difficulty by division, but 

 easily by seeds, which are sown in the open ground in 

 fall as soon as ripe, and covered an inch or so. They 

 will germinate the next spring, and, when two years 

 old, the seedlings may be removed to their permanent 

 positions, where they will flower the following year. 

 (J. B. Keller.) 



albus, Linn. (D. Fraxinella, Pers. Fraxinella alba, 

 Gaertn. F. Dictdmnus, Moench). A vigorous, sym- 

 metrical, hardy herb, with glossy leathery foliage sur- 

 mounted by long showy terminal racemes of good- 

 sized fragrant fls.: Ivs. alternate, odd-pinnate; Ifts. 

 ovate, serrulate, dotted with oil-glands: fls. white. 

 G.C. III. 34:409. Gn. 35:458; 68, p. 73; 75, p. 381. 

 G. 13:25. A.F. 5:328. Gng. 5:321. Var. purpftreus, 

 Hort., has large dark-colored fls. Var. r&bra, Hort., 

 has rosy purple fls., the veins deeper colored. Var. 

 giganteus, Hort. (D. giganteus, Hort.). Plant large. Var. 

 caucasicus (D. caucdsicus, Hort.), is a giant form with 

 racemes twice the length of those of the common kind 

 and standing well above the foliage. R.B. 32, p. 253. 

 Perhaps the same as var. giganteus. 



WILHELM MILLER. 



L. H. B.f 



DICTYOGRAMMA: Coniogramme. 



DICTYOSPERMA (Greek, netted seed). PalmAcese. 

 Areca-like palms, comprising several species of desirable 

 pinnate house and table palms that are becoming 

 deservedly well known. 



Slender spineless palms, with a ringed trunk: Ivs. 

 equally pinnatisect; segms. linear-lanceolate, acumi- 

 nate or bifid, the apical ones confluent; margins thick- 

 ened, recurved at the base; midrib and nerves promi- 

 nent, sparsely clothed with persistent scales beneath, 

 or naked; rachis and petiole slender, scaly, 3 -sided, 

 furrowed, sheath elongated, entire: spadix on a short 

 glabrous or tomentose peduncle, the branches erect 

 or spreading and flexuose, the lower ones with mem- 

 branaceous bracts at the base; spathes 2, complete, 

 dorsally compressed, papery, the lower one 2-crested; 

 fl.-bearing areas much depressed; bracts and bractlets 

 scaly; pistillate fls. rather large, white or yellowish: fr. 

 scaly, small, olive-shaped or subglobose. There are 

 6 or 8 species all from Trop. Asia but only the follow- 

 ing seem to be known in the trade. For cult., see Areca 

 from which Dictyosperma differs only in having a 

 1-celled and 1-seeded fr. 



alba, Wendl. & Drude (Areca alba, Bory. Ptycho- 

 sperma alba, Scheff.). Distinguished by the whitish 

 petioles and the whitish green veins of the Ivs. : caudex 

 about 30 ft. high, 8-9 in. diam., dilated at the base: Ivs. 

 8-12 ft. long; petiole 6-18 in. long, grooved down the 

 face; segms. 2*^-3 ft. long, 2-3 in. wide, 7-nerved; 

 veins and margins green or reddish: branches of the 

 spadix 6-18 in. long, erect or slightly reflexed, zigzag 

 when young. By far the best of the genus and rather 

 widely sold as Areca as is also D. rubra. 



aurea, Wendl. & Drude (Areca aurea, Hort.). Dis- 

 tinguished by the yellow or orange petioles and veins 

 of young plants: caudex about 30 ft. high, smaller and 

 more slender than the preceding: Ivs. 4-8 ft. long; peti- 

 ole 8 in. long; segms. 1^-2 ft. long, 1 in. wide; sec- 

 ondary veins scarcely visible: branches of the spadix 

 rigidly erect, 9-11 in. long. 



furfuracea, Wendl. & Drude (Areca furfuracea, 

 Hort.). Like D. rubra, but the petiole and If .-sheath 

 of the young plant tomentose. 



rftbra, Wendl. & Drude (Areca rubra, Hort.). Re- 

 sembling D. alba, but the Ivs. of the young plants 



