3480 



VIOLET 



VITEX 



are very poisonous. Divide the total amount of 

 cyanide into as many equal parts as there are jars used, 

 which latter should be one for every 50 to 75 lineal 

 feet of a house 12 to 18 feet wide. Put each part into 

 a two-pound manilla paper bag and this into a second 

 bag. Attach each package to a string or wire so arranged 

 as to allow it to be lowered from the outside of the 

 house into its respective jar. Pour into each jar an 

 amount of water about equal to the bulk of cyanide 

 in the bag, add commercial sulfuric acid until steam 

 is evolved, then from the outside lower the bags into 

 the jars beneath. Fumigate double varieties thirty min- 

 utes and single varieties twenty minutes, after which 

 open ventilators from outside, leaving them open at 

 least sixty minutes before entering the house. Aphides 

 may also be combated by using tobacco in some one of 

 its many forms, but tobacco is likely to weaken the 

 leaves and make them more liable to the attack of 

 fungi, and on this account is very objectionable. 



Red-spider (Tetranychus telarius) lives on the under 

 surface of the leaves, and, when present in sufficient 

 number, causes considerable damage. It is widely dis- 

 tributed on a great variety of plants, and when estab- 

 lished in the violet-house is most difficult to combat. 

 It can be held in check, and often the plants may be 

 kept entirely free from it, by frequent syringing with 

 clear water under a pressure of twenty to thirty pounds 

 to the square inch. Care must be taken to syringe 

 early in the morning and on bright days, so that the 

 plants may dry off before night. Neglect may be the 

 means of inducing disease. 



Eel-worms, or nematodes, are sometimes very injuri- 

 ous to the violet. A common species attacks the roots, 

 producing galls and distortions that check the growth 

 of the plants. These may be controlled by judicious 

 soil selection, the freezing of the soil in winter and 

 the use of good clean grass sod. A very destructive 

 nematode, Apheleuchus olesistus, that appeared in this 

 country twelve or fifteen years ago, is rapidly becom- 

 ing one of the serious enemies of the violet. This 

 nematode attacks the crown-buds, causing the plants 

 to "go blind." Rigid selection of stock is the only 

 remedy. Every "blind" crown plant should be taken 

 out and destroyed. Extreme care should be exercised 

 in bringing in new stock. Nearly all imported plants 

 are more or less affected with the pest. The bud nema- 

 tode does more injury in this country than abroad. 

 This may be due to the fact that while the pest has 

 been imported, its enemies have not been brought in. 

 Some very promising investigations are now being 

 made by N. A. Cobb, of the Bureau of Plant Industry, 

 United States Department of Agriculture, of a race of 

 predaceous nematodes which destroy immense num- 

 bers of the harmful kinds. 



In some parts of the country the larvae of gall-fly 

 (Diplosis violicola), violet sawfly (Emphytus canadensis), 

 greenhouse leaf-tyer (Phlyctcenia rubigalis), and several 

 species of cutworms (Agrotis et al.) injure the plants to 

 some extent by feeding on the foliage. Fumigating 

 with hydrocyanic acid gas is the best means of com- 

 bating them. 



Under certain conditions slugs, snails, sowbugs, and 

 the like, do considerable damage, especially to the 

 flowers. They also can be controlled by the hydro- 

 cyanic acid gas treatment. B . T. GALLOWAY. 



P. H. DORSETT. 



VIOLET, AFRICAN: Saintpaulia. V. Damask or Dame's: 

 Hesperis matronalis, V., Dog's-Tooth: Erythronium. V., Water: 

 Hottonia. 



VLRGILIA. (named for the poet Virgil). Leguminosse. 

 Tree sometimes grown in the greenhouse : Ivs. pinnately 

 compound; Ifts. small, without stipels; stipules narrow, 

 caducous: fls. rose-purple, in short terminal racemes; 

 calyx 2-lipped, upper 2-toothed, lower 3-toothed; 

 petals long-clawed; standard recurved, orbicular; 



wings ovate, falcate, keel shorter than the wings, 

 beaked; stamens free; ovary sessile: pod linear, piano- 

 compressed, leathery, 2-valved. One species, S. Afr. 

 V. capensis, Lam. (Podalyria capensis, Andr.). Tree: 

 Ivs. with 6-10 pairs of Ifts. which are linear-oblong, 

 mucronate, the young ones silky on both sides, the old 

 ones glabrous and glossy above: fls. rosy purple, J^in. 

 long; calyx silky, widely campanulate. S. Afr. B.M. 

 1590. 



V. liitea, Michx.=Cladrastis lutea. 



VIRGINIA COWSLIP: Mertensia mrginica. V. Creeper: Par- 

 thenocissus guinguefolia. V. Stock: Malcomia. 



VIRGIN'S BOWER: Clematis. 

 VISC ARIA: Lychnis. 



VISCUM (the old Latin name used by Virgil and 

 Pliny). Loranthacese. MISTLETOE. Parasitic shrubs 

 which grow on trees and are well known to all on 

 account of their use at Christmas. The Ivs. are some- 

 times flat and rather thick, sometimes reduced to 

 minute teeth or scales: fls. dioecious or monoecious at 

 the axils or nodes: berry 1-seeded, naked or crowned 

 with the perianth. About 70 species, natives of the 

 temperate and warmer regions. Two species deserve 

 mention: V. album, Linn. COMMON MISTLETOE (of 

 Eu.). Yellowish green, glabrous shrub, 1& ft. high: 

 Ivs. opposite or in whorls of 3, 1-3 in. long, obovate- 

 lanceolate, obtuse, 5-7-neryed: fr. white, nearly j^in. 

 diam., ovoid or globose, viscid. Eu. and Temp. Asia. 

 V. cruciatum, Sieber. Resembles V. album in habit, 

 foliage, and infl., but the Ivs. are very pale yellow-green 

 and 3-nerved: berries red-brown, larger and long- 

 pedicelled. Spain, N. E. Afr., and Syria. B.M. 7828. 

 See also Loranthus and Phoradendron. 



VISNEA (after a Lisbon merchant). Ternstroemidceae. 

 Evergreen tree with the habit and infl. of Eurya, some- 

 times grown in the warmhouse: fls. small, subsessile; 

 sepals 5, strongly imbricated, bases somewhat connate; 

 petals 5, imbricate, bases connate; stamens numerous, 

 adhering to the corolla at the very base; ovary 3-celled: 

 fr. an indehiscent berry, included in the enlarged and 

 fleshy calyx. One species, Canary Isls., little known 

 in cult. 



Mocanera, Linn. f. Tender evergreen shrub, 6-9 ft. 

 high, of compact habit and with dark green, shining 

 leathery foliage: Ivs. short-petioled, ovate-lanceolate, 

 serrate: fls. solitary, white, pendulous. Canaries. It is 

 a large evergreen shrub or small tree resembling in a 

 general way a tea plant or camellia. The specific name 

 Mocanera was given by the younger Linnaeus because 

 the fr. was supposed to be the "mocan" of the aborigines 

 which was made into a kind of sirup and used to a con- 

 siderable extent. The fls. are only % inch across, not 

 very numerous and much shorter than the Ivs., but they 

 are very sweet-scented. It has been offered in S. Calif. 



F. TRACY HUBBARD.! 

 VITELLARIA: Lucuma. 



VITEX (ancient Latin name for this or a similar 

 shrub). Verbenacese. Ornamental woody plants chiefly 

 grown for their white, blue, or yellowish flowers pro- 

 duced in terminal spikes or panicles. 



Deciduous or evergreen shrubs or trees: Ivs. opposite, 

 digitate, with 3-7, rarely with 1 1ft. : fls. in often pani- 

 cled, few- to many-fld. cymes; calyx campanulate, 

 usually 5-toothed; corolla tubular-funnelform, with 

 5-lobed, oblique and slightly 2-lipped limb; stamens 4, 

 2 longer and 2 shorter ones: fr. a small drupe, with a 

 4-celled stone. About 60 species are known, distributed 

 through the subtropical and tropical regions of both 

 hemispheres, few in the temperate regions. Some spe- 

 cies, particularly V. altissima and V. leucoxylon, in S. 

 Asia are important timber trees. 



