1468 



PYRACANTHA 



PYROLA 



ate greenhouse; also by layers and sometimes by graft- 

 ing on Hawthorn or Cotoneaster. Pyracantha is a genus 

 of 2 species from southeast Europe to the Himalayas; 

 closely allied to Cotoneaster but easily distinguished by 

 the crenulate Ivs. and the thorny branches, also by the 

 more conspicuous stipules. From Cratsegus it is chiefly 

 distinguished by the structure of the ovary, which con- 

 tains 2 equal ovules in each cell, while in Crataegus each 

 cell contains only one fertile ovule and a second imper- 

 fect and smaller one. Corymbs many-fld.; stamens 

 about 20, with yellow anthers : f r. red or orange, rarely 

 white, with 5 stones. 



coccinea, Roem. (Cotonedster Pyracdntha, Spach. 

 Cratvegus Pyracdntha, Borkh. MSspihis Pyracdntha, 

 Linn.). Fig. 2016. Shrub, attaining 6 ft., rarely 20 ft., 

 with numerous short spines : young branchlets and peti- 

 oles grayish pubescent: Ivs. oval-oblong to oblanceo- 

 late, acute, crenate, glabrous or slightly pubescent when 

 young, %-l/4 in. long: corymbs pubescent, many-fld., 

 about 1% in. broad : fls. small, white : fr. numerous, 

 bright red, about one-fifth in. across. May, June. Italy 

 to W. Asia.-Var. Lalandi, Dipp. (Cotonedster crenu- 

 Idta, Hort., not Wenzig), is of more vigorous growth, 

 with slender branches : Ivs. less deeply crenate: corymbs 

 larger: fr. bright orange-red. Well suited for covering 

 walls and said to be hardier than the type. Var. pauci- 

 flora, Dipp. Of low, dense habit and very thorny: co- 

 rymbs small: fr. yellowish red. Hardy and well suited 

 for hedges. Var. fructu albo is a form with white or 

 yellowish fruits. 



crenulata, Roem. (Cotonedster crenuldta, Wenzig. 

 Cratcegus crenuldta, Roxb.). Closely allied to the pre- 

 ceding: branchlets and petioles rusty-pubescent, gla- 

 brous at length: Ivs. narrower, oblong to oblanceolate, 

 obtuse or acutish, more leathery, bright green and glossy 

 above, 1-2 in. long: corymbs glabrous : fr. globose, bright 

 orange-red. May, June. Himal. B.R. 30:52. More tender 

 than the preceding, with handsomer, glossier foliage. 



ALFRED REHDER. 



section Hoffmann places the florists' chrysanthemums 

 (generally said to be the product of C. Indicum X 

 Sinense); also Pyrethrum roseum; also the white 

 weed or oxeye daisy, C. Leucanthemum ; the costmary, 

 C. Balsamita, var. tanacetoides ; and C. cineraricefolium 

 and corymbosum. Here also belong the Golden Feather, 



2016. Pyracantha coccinea (X 



PYRETHRUM in garden literature and language 

 nearly always means Pyrethrum roseum, the handsome 

 summer-blooming hardy perennial composite, with finely 

 dissected foliage, pictured on page 312 of this work, 

 Fig. 463. It is a favorite border plant in Europe, but 

 little known in America, although it has several hun- 

 dred varieties. It requires special culture, for which 

 see p. 310. Nearly all the Pyrethrums with personal 

 names, as Ajax, Ceres, etc., are forms of this species. 

 These varieties are also listed in catalogues as hybrid 

 Pyrethrums or P. hybridum. Although the genus 

 Pyrethrum was long ago reduced to the rank of a mere 

 section of Chrysanthemum, the name Pyrethrum is still 

 prominent in our nursery catalogues, and it has become 

 thoroughly established in the English language as the 

 common or popular name of Pyrethrum roseum and its 

 varieties, which are now referred by botanists to Chrys- 

 anthemum coccineum. 



In Engler and Prantl's Naturlichen Pflanzenfamilien, 

 Hoffmann makes eight sections of Chrysanthemum. 

 Among these the section Pyrethrum is distinguished, 

 chiefly, though not entirely, by the fact that the plants 

 are perennial and by the 5-10-ribbed akene. In this 



2017. Golden Feather. 



A common bedding plant with yellow foliage, often 

 catalogued as Pyrethrum parthenifolium, var. aureum. 

 See p. 311, species No. 4. 



Figs. 2017, 459, the well-known bedding plant with 

 golden foliage, and C. uliginosum, which has attracted 

 considerable notice within recent years. ^. M. 



PYBOLA (name said to be derived from Pyrus, name 

 of the pear tree). Ericaceae. WINTERGREEN. SHINLEAF. 

 Perennial evergreen, stemless herbs, with a cluster of 

 orbicular or elliptical leaves attached to the top of the 

 branching, slender, underground rootstocks: scape 

 angular and scaly-bracted, bearing racemes of white, 

 greenish or purple, nodding fls. in summer. Fls. slightly 

 irregular; sepals 5, imbricated; petals 5; stamens 10; 

 style declined or straight: capsule 5-lobed, splitting 

 from below upwards, bearing numerous small seeds. 

 The genus has about a dozen species and several varie- 

 ties, found in the north temperate zone from Great 

 Britain to Asia and North America south to Mexico. 

 About 10 species occur in North America. They grow 

 naturally in rather poor sandy uplands and in bogs. 

 Like many other members of the heath family, Winter- 

 greens are difficult to cultivate and will not succeed in 

 garden soil. In removing them from the woods, care 

 should be taken to secure a large ball of earth. They 

 may then succeed in the shade of evergreens and upon 

 rockeries in peaty soil. The species are scarcely in 

 general cult. ; they are offered by dealers in native 

 plants. P. rotundifolia is probably more cult, than the 

 others. For a fuller botanical account, see Gray's Syn. 

 Flora N. Amer. 



A. Fls. greenish; style straight. 



secunda, Linn. Height about 6 in.: Ivs. thin, ovate, 

 crenate, 1-1% in. long: fls. small, in a one-sided, dense, 

 spike-like raceme. North Atlantic states to Lab., Rocky 

 Mts. to arctic regions, N. Europe to Japan. 



AA. Fls. greenish white ; style curved downward. 



chlorantha, Swartz. Height 5-10 in. : Ivs. small, or- 

 bicular, dull, shorter than the petiole: fls. few; anther 

 cells with beaked tips. Lab. to Pa., Rocky Mts., north 

 to subarctic regions. 



elliptica, Nutt. Height 8-10 in. : Ivs. broadly oval or 

 oblong, thin, dull, serrulate, 2-2% in. long, longer than 

 the petiole; loosely 5-10-fld. Canada to Brit. Col. and 

 through N. Atlantic states to New Mex., Japan. 



picta, Smith. Height 5-10 in.: Ivs. thick, broadly 

 ovate to spatulate, blotched with white above, dull, 

 longer than the petioles. Pacific slope. 



AAA. Fls. white to pink or purple. 

 rotundi!61ia, Linn. Height 5-12 in. : Ivs. orbicular, 

 about 2 in. long, thick, shining above, shorter than the 

 petioles: fls. numerous: bracts conspicuous. Var. uli- 



