186 



THE DICTIONARY OF GARDENING, 



Folygfonum continued. 



ones sub-cordate at the base, upper ones truncate, all with 

 glaucous and prominently-veined under-surfaces. stem erect, 

 strong, h. 10ft. to 12ft. Sachalin Islands, 1869. A strong-grow- 

 ing, hardy perennial, differing chiefly from P. cuspidatum in its 

 angular, striated stems. This plant luxuriates in a moist subsoil 

 near the margin of water, and is a desirable subject for naturalising 

 in semi-wild places. See Fig. 228. (B. M. 6540.) 

 P. Sieboldii (Siebold's). A garden synonym of P. cuspidatum. 

 P. sphwrostacliyuin (round-spiked).* ft. blood-red, pendulous, 

 in a broad, cylindric, globose spike. Autumn. 1. 3m. to 5m. long, 

 linear, linear-oblong, or lanceolate, acute, crispidate crenulate, 

 glabrous and glaucous or pubescent beneath ; radical ones 

 stalked, cauline ones sessile. Alpine and sub-alpine Himalaya. 

 Hardy. (B. M. 6847.) 



P. tomentosum (tomentose). ft. clear rosy-pink, in erect, spike- 

 formed panicles at the tips of the branches. I. large, oblong- 

 lanceolate, very much attenuated at the apex, covered on bptn 

 surfaces, but especially beneath, with greyish hairs India, 

 1876. A half-hardy or greenhouse perennial. (R. G. 810.) 

 P. vaccinifolium (Whortleberry-leaved).* ft. bright rose, freely 

 produced in long, nearly round spikes. Late summer and autumn. 

 I. smooth, ovate or elliptic, attenuated at both ends, the margin 

 slightly revolute, bright green, sometimes tinged with red above, 

 pate beneath. Stems much-branching, woody, prostrate Hima- 

 laya, 1845. A hardy perennial, one o? the most useful plants for 

 rockwork in cultivation. (B. M. 4622.) 



POLTMNIA (dedicated to the muse Polyhymnia, 

 for no obvious reason, the species being coarse and 

 inelegant). Leaf-cup. ' OED. Composites. A genus com- 

 prising about a dozen species of greenhouse or hardy, 

 glabrous, scabrous-pubescent or villous, often slightly 

 viscid, perennial herbs, shrubs, or trees, natives of 

 America, from Bonaria to Canada. Flower-heads yellow 

 or yellowish, heterogamous, rather large, mediocre, or 

 small, corymbosely paniculate; achenes glabrous; in- 

 volucre hemispherical or expanded, with two-seriate 



FIG. 229. TUBERS OF POLYMNIA EDULIS. 



bracts ; receptacle flat. Leaves opposite, or the upper ones 

 alternate, often ample, entire, angulate, or lobed. The 

 species best known to cultivation are described below. 

 They are very useful for sub-tropical gardening in the 

 South of England. A warm position and deep, rich soil 

 are essential elements in their culture. Propagated freely, 

 in spring, by divisions ; by cuttings, struck in sand, in a 

 gentle heat, during January; or by seeds, sown in heat, 

 at the same time. 



Polymnia continued. 



P. canadensis (Canadian), fl.-heads whitish-yellow, small ; rays 

 few, obovate or wedge-shaped, shorter than the involucre. July. 

 I., lower ones deeply pinnatifld, the uppermost ones triangular- 

 ovate, and three to flve-lobed or angled, petioled. h. 6ft. North 

 America, 1768. Hardy herbaceous perennial. 



P. cdulis (edible), fl.-heads yellow. A tall, coarse-growing, hardy 

 perennial, cultivated in the Andean region for the sake of its 

 edible tubers. See Fig. 229. 



P. grandls (large). A synonym of Montanoa bipinnatifida. 



P. heracleifolia (Heracleum-leaved). A synonym of Montanoa 

 bipinnatifida. 



P. pyramidalis (pyramidal), fl.-heads having a yellow ray and 

 a dark brown disk, disposed in cymes. Summer and autumn. 

 1. cordate-ovate, 12in. long by 16in. broad, with decurrent petioles. 

 h. 10ft. A free and rapid-growing, half-hardy, arborescent 

 perennial, something like the Sunflower in habit. New 

 Grenada, 1867. (R. H. 1867, 210.) 



P. Uvedalia (Uvedalia). fl.-heads yellow ; rays ten to fifteen, 

 linear-oblong, much longer than the inner scales of the involucre ; 

 outer involucral scales very large. September. I. broadly ovate, 

 angled and toothed, nearly sessile ; lower ones palmately lobed, 

 abruptly narrowed into a winged petiole, h. 4ft. to 10ft. United 

 States, 1699. Hardy herbaceous perennial. 



POLYPAK/A. A synonym of Honttuynia (which 

 see). 



FOLYFETALOUS. 



tinct. 



Having petals perfectly dis- 



POLYPHEMA. A synonym of Artocarpus. 



POLYPODIUM (the old Greek name, used by Theo- 

 phrastns, from polys, many, and podion, a little foot ; on 

 account of the appearance of the rhizome and its append- 

 ages). Polypody. Including Aglaomorpha, Calymmodon, 

 Campyloneuron, Colysis, Craspedaria, Cryptosorus, Cyrto- 

 miphlebium, Dibblemma, Dictymia, Dictyoptens, Drynaria, 

 Dryostachyum, Goniophlebium, Goniopteris, Grammitis 

 (in part), Lecanopteris, Lepicystis, Lopholepis, Micro- 

 gramme, Microsorium (in part), Monachosorum, Nipho- 

 bolus, Niphopsis, Paragramma, Phegopteris, Phlebodium, 

 Phymatodes, Pleopeltis, Pleuridium, Polycampium, Pseuda- 

 thyrium, and some other less important so-called genera. 

 OBD. Filices. The largest genus of the order, comprising 

 upwards of 450 species. It includes plants of two 

 different modes of growth, each series comprising a num- 

 ber of species of each of the different kinds of venation, 

 and from all climates. Sori on the back of the lobes, 

 round or rarely oblong, not more than twice as long as 

 broad. Polypodiums are very handsome plants ; they 

 thrive under very varied conditions. Many of them, per- 

 haps, do best in good fibrous loam and soil rich in humus ; 

 others thrive on blocks of fibry peat, on tree-fern stems, 

 or treated as basket-plants. Some of them are eminently 

 adapted for crevices on rockwork. Except where other- 

 wise stated, the species described below thrive under 

 stove treatment. For general culture, &c., see Ferns. 



P. acrostichoides (Acrostichum-like). rhiz. woody, wide-creep- 

 ing, scaly, black in the centre, sti. lin. to Sin. long, firm, erect. 

 fronds lit. to 2ft. long, iin. to lin. broad, ligulate, gradually nar- 

 rowed below, naked above, dirty-white-tomentose beneath, sori 

 bright-coloured, not immersed, small, close, covering the whole 

 upper part of the frond. Ceylon, Queensland, &c. Greenhouse. 

 SYN. Siphobolus acrostichoides. 



\ P. adnascens (adnascent). rhiz. slender, firm, with linear, de- 

 ciduous scales, sti. Jin. to lin. long, firm, erect, fronds dimor- 

 phous ; the barren ones elliptical or spathulate, blunt ; the fertile 

 ones longer and narrower, 6in. to 12m. long, Jin. to pn. broad, 

 naked above, white-tomentose beneath. sori bright-coloured, 

 small, immersed, occupying the whole of the contracted upper 

 part of the frond. India, &c., 1824. SYN. Siphobolus adnascens 

 (H. G. F. 19). 



P. adnatum (adhering), sti. 6in. to 12in. long, naked, glossy. 

 fronds lift to 3ft. long, 1ft. broad, with an oblong-lanceolate, 

 entire fertile pinna, 6in. to 9in. long, and Hin. to 2in. broad, and 

 several similar lateral ones on each side, the upper ones broadly 

 adnate to the rachis at the base, sori and areolce in rows of four 

 to six between the midrib and edge. Guatemala, &c. SYN. 

 Goniophlebium adnatum. 



P. albo punctatissimum (much dotted with white). A variety 

 of P. crassifolium. 



P. albo-squamatum (white-scaly).* rhiz. woody, with dark 

 brown scales, sometimes lin. long. sti. 6in. to 12in. long, firm, 

 erect, glossy, fronds sometimes simple, usually pinnate, 1ft. to 



