2708 



PLATANUS 



PLATYCERIUM 



pyramidalis, Jaen. (P. pyramidalis, Bolle). Of pyram- 

 idal habit: Ivs. usually 3-lobed, often longer than 

 broad, with usually rounded base. Var. tubifera, 

 Jaen. (P. superba, Hort.). With very conspicuous 

 elongated, tubular stipules. There are also some forms 

 with variegated Ivs. Var. Suttneri, Hort., with the Ivs. 

 spotted and marked white, and var. Kelseyana, 

 Schneid. (var. aureo-variegata, Hort.), with yellow- 

 variegated Ivs. The London plane is more generally 

 planted under the name of the oriental plane than the 

 true P. orientalis. It resembles in foliage more the 

 American plane and is of more pyramidal habit than 

 the oriental plane, which in its typical form has a 

 broad head, with wide-spreading branches, deeply 

 divided, 5-7-lobed Ivs., and the fr. -heads usually in 

 3's and 4's. It is somewhat hardier than the oriental 

 plane. 



occidental's, Linn. BTJTTONWOOD. BUTTONBALL. 

 AMERICAN PLANE-TKEE. Also wrongly called SYCA- 

 MORE. Fig. 3063. Large tree, attaining 130 or 

 occasionally 170 ft., with a round-topped oblong or 



3063. Platanus occidentalis. (XK) 



broad head and with a trunk 10 ft. or exceptionally 

 more in diam., often of considerable height: bark of 

 limb and branches of very light often almost creamy 

 white color, at the base of the trunks dark brown, 

 fissured: stipules large, with toothed margin: Ivs. as 

 broad or broader than long, truncate or cordate, rarely 

 cuneate at the base, usually 3-, sometimes 5-lobed, with 

 shallow sinuses; lobes shorter than broad, coarsely 

 toothed or entire, floccose-tomentose when young, at 

 maturity only pubescent on the veins beneath, 4-9 in. 

 broad: fr .-heads solitary, rarely in 2's, on 3-6-in.-long 

 peduncles, about 1 in. across or more, comparatively 

 smooth at length; nutlets with obtuse apex, with the 

 rest of the style r&in. long or shorter. May. Maine to 

 Ont. and Minn., south to Fla. and Texas. S.S. 7:326, 

 327. G.F. 2:354, 355; 9:55. Em. 1:261, 263. Gng. 

 4:343. Mn. 3, p. 69; 5, pp. 205, 209. The most massive 

 and perhaps the tallest of all deciduous trees of N. 

 Amer. and an excellent street and park tree where it is 

 not injured by fungous diseases. A doubtful variety is 

 var. hispanica, Wesmael (P. hispanica, Lodd.). Lvs. 

 large, 3-5-lobed, with very shallow sinuses, coarsely 

 toothed, usually cordate at the base. Gn.l, p. 588; 20, 

 p. 370. The P. densicdma, Dode (B.S.D. 1908:68), 

 described as having usually truncate or broadly cuneate 

 Ivs. and 1-3 heads with acutish nutlets is probably not 

 different from P. occidentalis or may belong to P. 

 acerifolia. 



P. milgctris, Spach, comprises all species of the genus. P. 

 Wrightii, Wats. Tree, to 80 ft., often divided into several sts.: 

 Ivs. usually cordate or truncate, deeply 3-7-lobed, with lanceolate, 

 acuminate, entire or dentate lobes, tomentose beneath or nearly 

 glabrous at length, 6-8 in. long: fr.-heads racemose, rather smooth, 

 each on a short stalk. New Mex. and Ariz, to Calif. S.S. 7:329. 



The other species, as P. mexicAna, Moric., which is sometimes 



planted as a street tree in Mex., P. Lindeniana, Mart. & Gal., 

 and P. glabrata, Fern., all natives of Mex., are not yet intro. 



ALFRED REHDER. 



PLATONIA (from a personal name) . Guttiferse. Trees, 

 little known as yet in cult. : Ivs. leathery, closely and 

 finely feather- veined: fls. large, rose, solitary, termi- 

 nal, perfect; sepals 5, imbricate; petals 5, much larger 

 than the calyx, scarcely convolute into an ovoid 

 corolla; stamens 5; ovary 5-celled: fr. a fleshy indehis- 

 cent 5-celled edible berry. Two species from Brazil. 

 P. insignis, Mart. Large tree: Ivs. coriaceous, oblong, 

 acute: fls. solitary, terminal, showy; sepals suborbicu- 

 late, 2 outer smaller; petals broad-ovate, rose outside, 

 white inside; ovary ovoid: berry subglobose or oval. 

 Brazil. Intro, and distributed by the U. S. Dept. of 

 Agric. 



PLATYCARYA (Greek for broad, and nut; alluding to 

 the shape of the fruit). Syn., Fortunxa. Juglandacese. 

 A monotypic genus distinguished from all other Jug- 

 landaceae by its fertile fls. forming an upright cone-like 

 spike. Small deciduous tree: the branches with 

 solid pith: winter buds with imbricate scales: 

 Ivs. odd-pinnate, similar to those of Carya Pecan, 

 but smaller: staminate catkins axillary; pistil- 

 late terminal, solitary: fr. a small, winged nut 

 in the axils of densely imbricated, rigid and 

 sharply pointed lanceolate bracts forming a 

 terminal upright cone. Rarely cult, and not 

 hardy north of the Middle states. It has grace- 

 ful foliage, but its ornamental value is not great. 

 Prop, by seeds and by layers, probably also by 

 grafting on Carya. 



strobilacea, Sieb. & Zucc. (Fortunsea sinen- 

 sis, Lindl.). Small tree, with upright glabrous 

 branches: Ivs. 8-12 in. long; Ifts. 9-17, sessile, 

 oblong-lanceolate, falcate, acuminate, doubly 

 serrate, pubescent only on the midrib beneath, 

 3-4 in. long: fr.-bearing cone about 1-1 3^ in- 

 long, oval, brown. Summer. Japan, China. S.Z. 

 2:149. F.S. 4, p. 3266. R.H. 1888, p. 88. J.H.S. 

 1846, p. 151. S.I.F. 1:17. ALFRED REHDER. 



PLATYCERIUM (Greek, broad horn; alluding to the 

 shape of the Ivs.). Polypodiacese. STAG-HORN FERN. 

 An anomalous genus of ferns with irregularly lobed 

 thick Ivs. with the sori forming irregular patches over 

 one or both surfaces. The sterile Ivs. are flat, rounded 

 expansions closely adherent in layers to the substratum. 

 In their native forests these ferns grow to the surface of 

 trees and old plants and often form enormous nests. 

 A few kinds of Platycerium are offered for sale in Amer. 

 European growers list others, new ones appearing from 

 time to tune, but the whole group is grown in America 

 only as specimens in large collections. The word 

 "disk," as used below, refers to the widest unbranched 

 portion of the fertile frond. 



The stag-horn ferns are amongst the most beautiful 

 and distinct of ferns perhaps the most striking of all 

 because of their noble antlered appearance and their 

 epiphytal habit. They have two kinds of fronds, bar- 

 ren and fertile, the former being rounded disks which 

 clasp the tree trunk, while the fertile fronds generally 

 hang down and look like antlers. Occasionally the 

 barren fronds are more or less antlered, as in P. grande, 

 but never give so perfect a suggestion as do the fertile 

 fronds. The species are all tropical, except P. alcicorne, 

 which is therefore the easiest to grow and the common- 

 est in cultivation. This species can endure a night 

 temperature of 50 F. or even less. The glory of the 

 genus, however, is P. grande (Fig. 3064). The barren 

 fronds are exceptionally large, rounded, and wavy 

 margined at the base, deeply cut above, forming an 

 erect or arching background to the pendent fertile 

 fronds, which fork more times and have much narrower 

 segments than the barren fronds. Unfortunately this 



