An Encyclopedia of Horticulture. 



379 



Scale Insects — continued. 

 plants, to whiuh they are often very destructive. Some 

 broods consist wholly of females, and other.^ of both 

 sexes. Their rate of increase is much below that of 

 the Aphides, there being-, in most of the species, only 

 one brood in the year. 



The number of species already recorded as injurious to 

 cultivated plants, especially in the warm zones, is too 

 larg-e to permit of more than a brief mention here of some 

 of the more important kinds. They have been divided, 

 by means of comparatively minute characters, into 

 numerous g-enera ; some of the species live upon several 

 kinds of plants, and, on the other hand, many plants 

 support various kinds of these insects. The latter are 

 so much alike as to render it vain to attempt here to 

 state clearly the differences between the species, as 

 these are found in minute structural characters ; nor, 

 indeed, is this necessary, since the same remedies are 

 serviceable against all of them, and are most successful 

 when directed against the larva?. In Great Britain, Scale 

 Insects are far more numerous, and are usually more 

 injurious, in glass houses than in the open air. But 

 among the "' outdoor " kinds the following must be 

 noted : 1. Apple Mussel Scale, or Oyster-shell Bark 

 Louse {Aspidiiitus concliifonnis or Myfilatipim pnmorntn), 

 like single valves of very small mussel-shells adherent 

 to the branches of Apple-trees ; they occur on both 

 sides of the Atlantic. "2. Pear Oyster Scale {Diaspis 

 ostrectformit!) very like the Apple Mussel Scale but of 

 smaller size. 3. Rose Scale {D. Kosce), like a white, 

 scurfy coat on twigs and stems of Roses, especially of 

 cultivated kinds, -i. Camellia Scale [Aspiiliotus Camelliiv), 

 on buds and bracts of Camellias. 5. Spindle-tree Scale 

 {Cliionanpis Euotiymi), so abundant on Eiionymuit Japo- 

 niciit;, near Montpellier. in France, as to threaten the 

 existence of the shrub. Several species are found in 

 Britain in greenhouses, where they frequently do very 

 great harm. Among the more hurtful are: AtipiiHotut: 

 Nerii, on Acacias, Lemons, Oleanders, &c. : A. palmarum, 

 on Palms and Cycads : Lecaniiim He^periihim (.see Fig. 

 441), on Orange leaves, or on other food - plants {e.y., 

 MyrtacecB) ; and Dactylopius adonidum, on most green- 

 house plants. 



Many others have been described as very hurtful, 

 especially by Professor Comstock in his '* Report on 

 Scale Insects " ; and probably a number of these will 

 be found in English greenhouses, e.g.^ Darfylopiua lonyi- 

 flis, on Ferns and EupliovbiacecB ; D. destructor, on 

 Coffee. Oranges, and, in fact, almost every greenhouse 

 plant; (.'eroplastes jtorideni>ig, on Oranges, &c. ; but for 

 a full account of these the reader is referred to the 

 above-mentioned work. 



Remedies are two-fold, viz., natural and artificial. The 

 best natural remedy is to encourage the multiplication 

 of certain minute insects belonging to the great divi- 

 sion Hymennpieni. which are parasitic in the Scale 

 Insects, and destroy large numbers of them. It has 

 been found useful to carry branches bearing Scale 

 Insects infested with parasites to localities where the 

 parasites did not previously exist, inasmuch as they soon 

 multiply, and produce a marked effect on the number of 

 Scale Insects. 



Artificial remedies are numerous. Among the most 

 useful are the following : Soap solution {^Ib. of soap in 

 one gallon of water) or kerosene solution (about one gill 

 in five gallons of water), syringed or sprayed over the 

 plants every second day ; phenyle, in a strength of from 

 three to six teaspoonfuls to four gallons of water, applied 

 at intervals of eight days ; alkaline washes, such as concen- 

 trated lye of wood-ashes or of coarse potash, which, used 

 with a brush, frees the branches from the insects; strong 

 solution of tobacco ; and animal oils, e.g., whale oil. The 

 last-named suffocate the insects by closing the breathing 

 pores along the sides of their body. 



SCALi: OB SCALT FERN. Srr Aspleninm 



Ceterach. 



SCALES. A term applied to close-pressed, small, 

 ru<Umentary leaves, resembling minute scales, or to any 

 thin, scarious bodies. 



SCALIA. A synonym of Fodolepis (which see). 



SCAIiLION. A common name for Allium aHcalunirum 

 Dinjii.'i. Tlie term is also generally applied to all Onions 

 that do not bulb, but form long necks like Leeks. 



SCALPS ItLIFOKIVI. Resembling the blade of a 

 penknife, but ]ilai.'ed vertically on a branch. 



SCAMMONT-FLANT. See Convolvulus Scam- 

 monia. 



SCANDENT. Climbing. 



SCAFE. A long, naked or nearly naked peduncle, 

 rising from the crown of a root. 



SCAPH7GLOTTZS (from shtphe, a boat, and 

 glotta, a tongue ; in allusion to the hollowed labellum). 

 Boat-lip Orchid. Syn. Cladobium. Ord. Orchiden-. A 

 small genus (about eight species) of stove, epiphytal, 

 branched orchids, natives of tropical America. Flowers 

 small, twin or few in a fascicle ; lateral sepals prolonged 

 at the base, and often connate with the foot of the rather 

 long, erect column; petals similar but smaller; lip 

 narrow, continuous with the column, bat turned up so 

 as to be parallel with it ; pollen masses four, cohering 

 in pairs. Leaves narrow, sometimes linear, coriaceous. 

 Stems slender, straggling. Pseudo-bulbs borne in the 

 axils of the leaves. Only two of the species are known 

 to gardeners. These require similar culture to Cattleya 

 (which .^iee). 



S, stellata (star like). This species only differs from .S". violacea 

 ill having; ]urj;er fluwers, with more sjireaiUuK segments, and 

 the latenil lobes of the lip as large as the middle one. Deme- 

 rara. 

 S. Violacea (violet), ff. violet, minute, borne on very short 

 peduncles ; lateral sepals produced, oblique, twice as broad as 

 the iipperone; lip white, fleshy, rhaimelled. /. 2in. to 3in. long, 

 linear or linear-lanreolate. emarjiinate. Stems terete, striated, 

 articulated. Denierara. (11. M. 4071 ; B. R. 1901.) 



SCAFIFOKM, SCAFOSE. Resembling a scape. 

 SCAFZGEROUS. Scape-bearing. 



SCAR. The mark left on a stem by the separation 

 of a leaf; or on a seed, Ac, by its detachment. 



SCARCE UMBER MOTH. See Hybernia. 



SCARIOLE. An old name for Endive (Cichorium 

 Endiria). 



SCARIOUS. SCARIOSE. Thin, dry, shrivelled, 

 membranous; e.g., the involucral leaves of many species 

 of Cent a urea. 



SCARLET RUNNER. See Beans and Fhaseolus 

 vulgfaris multiflorus. 



SCARLET STRAWBERRY. See Pragaria 

 virg'iniana. 



SCATTERED. Not regularly disposed; i.e., not 

 whorled, opposite, or ternate, &c. 



SCELOCHILUS (from skelos, a leg, and rheiloit, a 

 lip ; in reference to the shape of the divided labellum). 

 Ord. Orchideir. A small genus (three or four species) 

 of stove, epiphytal orchids, natives of the Andes of South 

 America. Flowers mediocre, few in a raceme, pedicellate ; 

 sepals erect, connivent, the posterior one concave, the 

 lateral ones connate, produced in a sac or spur; petals 

 rather broader than the posterior sepal; lip continuous 

 with the base of the column, long-clawed, erect ; column 

 erect, semi-terete ; pollen masses two, sub-globo.se ; bracts 

 narrow ; scapen at the base of the pseudo-bulbs, erect, 

 simple or slightly branched. Leaf coriaceous, not plicate. 

 Stem at length more or less thickened into a narrow 



