AN ENCYCLOPEDIA OF HORTICULTURE. 



155 



FLANERA (named in honour of I. J. Planer, a Ger- 

 man botanist, who published a Flora of Erfurt, in 1788). 

 OBD. Urticacece. A monotypic genus. The species is a 

 hardy, deciduous, unarmed tree, probably not now in 

 cultivation in Britain. It requires culture similar to 

 Ulmns (which see). 

 P. aqnatica (aquatic). Planer-tree, n. brown, clustered; perianth 



four or five-fid. March and April, fr. nut-like, oblique, ovate, 



compressed, wingless. 1. lin. to lAin. long, alternate, distichous, 



shortly stalked, serrated, ovate, acute, roughish, penniveined ; 



stipules free, caducous, h. 20ft. to 30ft. Southern United States, 



1816. SVN. P. Gmelini. 

 P. Gmelini (Gmelin's). A synonym of P. aquatica. 



PLANER-TREE. See Planera aquatica. 



PLANE-TREE. See Platanus. 



PLANE-TREE, SCOTCH. A general name in 

 Scotland for Acer Pseudo-platanus. 



PLANTAGINEJE. A natural order of herbs, some- 

 times annual or perennial, almost stemless or stolon- 

 bearing, sometimes shortly caulescent, branched or suf- 

 fruticose, glabrous, simply pilose, or woolly in the axils ; 

 they are natives of the temperate regions of both hemi- 

 spheres, especially in Europe and North America, and 

 are but rarely met with in the tropics. Flowers regular, 

 hermaphrodite or monoecious, small, in elongated or 

 shortened spikes, or rarely solitary and sessile in the 

 axils of the often scarions bracts ; calyx four- parted, 

 with closely-imbricated segments, persistent in the fruit ; 

 corolla hypogynous, gamopetalons, scarious, marcescent, 

 with an ovoid or cylindrical tube, and four speading, im- 

 bricated lobes, sometimes wanting in the female flowers ; 

 stamens four, or fewer. Fruit a one or more celled, one or 

 more seeded, membranous capsule, stipitate or included. 

 Leaves radical, or in the caulescent species alternate, 

 rarely opposite, one to many-nerved, entire, toothed, or 

 pinnatifid, sometimes sheathed ; petioles usually dilated 

 at the base, and accompanied by a woolly membrane. 

 Several species of Plantago are employed in medicine. 

 The order comprises only three genera Bougueria, Litto- 

 rella, and Plantago and perhaps about 200 species. 



PLANTAGO (the old Latin name of the genus, nsed 

 by Pliny). Plantain. OBD. Plantaginece. This genus com- 

 prises all the species of the order (which see for characters) 

 save two. They are of very little importance from a 

 garden standpoint. P. Coronopus, P. lanceolata, P. major, 

 P. maritima, and P. media, are British plants. P. brasil- 

 iensis is sometimes seen in botanic gardens. All thrive 

 in ordinary soil, and may be readily raised from seed ; 

 the perennial species may also be propagated by division. 

 P. brasiliensis (Brazilian). JL whitish, disposed in a compact, 



cylindrical spike, about Sin. long: scape axillary, solitary, rounded, 



twice as long as the leaves, clothed with white, adpressed hairs. 



Summer. I. linear-lanceolate, smooth, three-nerved, entire, with 



the margins somewhat thickened, much narrowed towards the 

 "base, and dilated again at the stem, which they embrace, h. 1ft. 



Brazil, 1823. (B. M. 2616.) 



PLANTAIN. See Plantago. The name is also 

 applied to other plants. 



PLANTAIN LILT. A common name for Funkia. 



PLANTAIN-TREE. See Musa. 



PLANTAIN-TREE, MAURITIUS. See Musa 

 rosacea. 



PLANT -BOXES AND CASES. Plant -boxes 

 are used for large trees or shrubs that cannot be pro- 

 vided with pots of sufficient size to contain the roots. 

 They are usually made of wood, but sometimes of slate, 

 and the sides may be constructed so as to be movable, 

 for allowing the roots and drainage to be examined, 

 should it become necessary. Boxes made of slate have 

 the advantage of great durability, and they are readily 

 kept clean. Special provision should be made to in- 

 sure drainage, and Boxes containing trees of large dimen- 

 sions should, for this reason, be stood on something to 

 keep them a little above the ground level. Plant or 

 Cutting-boxes, about Sin. deep, for raising seedlings and 



Plant-boxes and Cases continued. 

 growing-on tender bedding plants, are extremely useful; 

 they answer well if the wood is merely planed over 

 before being made up. 



Boxes for window plants should bo about Gin. deep : a 

 less depth does not afford room for sufficient soil to 

 sustain the plants for a season. 



Plant-cases used outside windows, and also in rooms, 

 require their occupants renewed occasionally, but not 

 very frequently, if flowering plants are excluded. Many 

 of the hardier species of Palms, greenhouse Ferns, 

 Selaginellas, &c., are admirably adapted for the decora- 

 tion of Plant-cases; tender or delicate subjects should 

 not be included, unless the Cases are utilised for special 

 purposes inside a glass structure. 



An inclosed portion of a propagating-house, wherein 

 cuttings of larger than ordinary size are inserted, is 

 also termed a Plant or Propagating-case. 



FLANTIA. Included under Hexaglottis. 



PLANTING-. See Transplanting. 



PLANT LICE. See Aphides. 



PLANT MITES. See Mites. 



PLANT - PROTECTORS. These are very nume- 

 rous, as the term is applicable to anything which acts, 

 if only temporarily, to preserve plants from injury. 

 Bell glasses, handHghts, small movable frames, and 

 even panes of glass, amongst many other things, may be 

 termed appliances for plant-protection, when they are 

 used as such to ward off heavy rains or severe frost. 

 Full information will be found under Bass or Bast 

 Mats, Bell Glasses or Cloches, Cocoa-nut Pibre 

 Refuse, Frames, Glass, Hand Glasses, Netting, 

 Straw, Willesden Paper, &c. 



PLASMODIOPHORA BRASSIC2B. This is the 

 cause of the disease known as " Clubroot," sometimes 

 called also " Finger-and-Toe," in Turnips, Cabbages, 

 Charlock, and other species of the genus Brussica, and 

 also in Raphanus Raphanistrum, or Wild Mustard. It 

 is a Fungus of very simple structure, and belongs to the 

 carious group called Myxomycetes, the species in which, 

 while vegetating, consist of minute, naked masses of 

 protoplasm, endowed with a power of movement, by 

 changing their forms, like the low microscopic animals 

 called Amoebae. These small, naked masses tend to unite 

 when they meet, and thus they increase in size, and 

 form what are called plasmodia. In some of the species?, 

 the plasmodia may reach a size of 2in. or more in breadth, 

 and resemble a mass of clear or muddy-looking jelly. 

 After a time, the plasmodia become covered with a firm 

 coat, and break up into myriads of small, round cells, or 

 spores, each inclosed in a cell-wall. These spores may 

 remain for a time unchanged; but, under favourable 

 circumstances, they burst, throw off the cell- wall, and 

 appear as very minute plasmodia, which go through the 

 same development as before. Almost all the Myxomycetes 

 live on decaying organic matter, but P. Brassicce does 

 not. Its plasmodia are always minute, and they pene- 

 trate into the tissues of its hosts. The roots of a plant 

 attacked by "Finger-and-Toe" vary considerably in ap- 

 pearance, according to the stage of the attack. The 

 branch-roots very often bear swellings much exceeding 

 the proper thickness of these roots. The swellings 

 are usually spindle-shaped or roundish ; at first, they are 

 nearly smooth, but after some time they become rough. 

 The main root is also often injured, as shown by its 

 enlarged size, and, frequently, by its roughly- fingered 

 appearance. In the autumn, and as winter advances, 

 the diseased portion becomes more and more pulpy and 

 decayed, and is also overgrown with other Fungi, which 

 find their food in the rotting mass. Towards the end 

 of winter, only the woody bundles of the roots remain 

 moderately firm, the cellular tissues having dried up, 

 and resembling coarse dust. 



