1368 



PL AT AN US 



PLATYCERIUM 



ciniata, Hort. ). Lvs. cuneate or truncate or cuneate 

 at the base, deeply 5-lobed, with narrow, elongated, 

 coarsely toothed lobes. Gn. 1, p. 572, 573; 20, p. 371. 

 Var. undulata, Ait. (var. cuneata, Loud. P. cuneata, 

 Willd.). Often shrubby : Ivs. short-stalked, smaller, 

 usually deeply 3-lobed and cuneate, with narrow-toothed 

 lobes. Gn. 1, p. 618; 20, p. 371. 



P. racemdsa, Nutt. (P. California, Benth.). Tree, to 100 or 

 120 ft., with a trunk often divided into several stems: Ivs. usu- 

 ally cordate or truncate, deeply 3-5-lobed, with ovate-lanceo- 

 late, mostly entire lobes, pale-tomentose beneath, 6-10 in. long: 

 fr. -heads bristly, sessile on the slender stalk, racemose. Calif. 

 S.S. 7:328. P. vulgaris, Spach, comprises all species of the ge- 

 nus. P. Wrlghtii, Wats. Tree, to 80 ft., often divided into 

 several stems : Ivs. usually cordate or truncate, deeply 3-7- 

 lobed, with lanceolate, acuminate, entire or dentate lobes, to- 

 mentose 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 some- 

 times planted as a street tree in Mexico, P. Lindeniana, Mart. 

 & Gal., and P. glabrdta, Fernald, all natives of Mex., are not 

 .yet introduced. ALFRED REHDEB. 



PLATYCABYA (platys, broad, carya, nut; alluding 

 to the shape of the fruit). Syn., Fortunea. Juglanda- 

 cece. A monotypic genus distinguished from all other 

 Juglandaceae 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 Hicoria Pecan, but smaller; 

 staminate catkins axillary; pistillate terminal, solitary: 

 fr. a small, winged nut in the axils of densely imbri- 

 cated, rigid and sharply pointed lanceolate bracts form- 

 ing a terminal upright cone. Rarely cult, and probably 

 not hardy north of the Middle States. It has graceful 

 and interesting foliage, but its ornamental value is not 

 great. Prop, by seeds and by layers, probably also by 

 grafting on Hicoria. 



strobilacea, Sieb. and Zucc. (Fortunea SinSnsis, 

 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% in. long, oval, brown. Summer. Japan, China. 

 :S.Z. 2:149. F.S. 4, p. 326b. R.H. 1888, p. 88. 



ALFRED REHDER. 



PLATYCERIUM (Greek, broad horn; alluding to the 

 shape of the Ivs.). Polypodiacece. 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. 



Eight kinds of Platycerium are offered for sale in 

 America. The word "disk,' as used below, refers to the 

 widest unbranched portion of the fertile frond. 



A. Plants not forked like a stag hom...l. Angolense 

 JLA.. Plants resembling a stag horn. 



B. Sori borne on a special receptacle 



described under No. 2 2. biforme 



BB. Sori borne on the last forks or near 



their base. 

 c. Barren fronds stag -horn -like 



above. 



D. Fertile fronds in pairs. 

 E. Plants glabrous or nearly 



so 3. grande 



EE. Plants pubescent, with yel- 

 lowish wool 4. Wallichii 



DD. Fertile fronds in 3* s 5. Willinckii 



CC. Barren fronds not stag -horn- 

 like, entire or merely lobed. 

 D. Segments and simises of the 



fertile fronds very broad... 6. jfithiopicum 

 .DD. Segments and sinuses narrow. 

 E. Unbranched portion of fer- 

 tile fronds very long and 



narrow 7. Hillii 



EE. Unbranched portion of fer- 

 tile fronds moderately 

 long 8. alcicorne 



1. Angolense, Welw. (P. JEthiopicum, var. Angolense, 

 Welw.). Fertile fronds wedge-shaped in outline and 

 merely wavy at the margin. It is also distinct by reason 

 of ,f elt-like covering of rust-colored wool on the lower side 

 of the fronds. Barren fronds large, erect; fertile fronds 

 attaining a length of 18 in. and a width of 9 in. at the 

 top: spore-mass nearly as broad as the frond. Angola 

 (West Africa). G.C. III. 23:155 (repeated in 28:444). 



2. biforme, Blume. According to Blume's plate and 

 description, this differs from all other kinds in having 

 the spores borne on a special appendage, which is kid- 

 ney-shaped and attached below the first fork. Blume 

 says there are 2 such appendages ; that the barren 

 fronds are roundish, entire below, lobed above: fertile 

 fronds 3-5 ft. long, many times forked, pale green. 

 Java. The fertile fronds of P. biforme are said to grow 

 15 ft. long sometimes. The picture in Gn. 4, p. 295, 

 labeled P. biforme seems to be distinct and anomalous, 

 though somewhat like P. grande. 



3. grande, J. Smith. Fig. 1848. This may be readily 

 distinguished from P. alcicorne by its barren fronds, 

 which are also stag-like, while those of P. alcicorne are 

 not. Barren fronds stalkless ; segments blunt, spongy, 

 pale green, tomentose: fertile fronds in pairs, 3-6 ft. 

 long: sori not at the base of every ultimate fork but 

 against the upper edge of the disk, with an infertile 

 fork projecting beyond on either side. North Australia. 

 G.C. 1872:1137; III. 8:97 (good, repeated in III. 10:698 

 and 28:433). Gng. 5:169 (same as A.F. 6:701). F. 

 1850:47 (same as F.S. 6, p. 156). Not G.M. 40:135, 

 which is P. ^Kthiopicum. Mn. 1, p. 77 (erroneously as 

 P. alcicorne). 



4. Wallichii, Hook. As in P. grande, the sori are 

 borne not at the base of the ultimate forks, but on a 

 disk which is not squared off at its upper surface but 

 rounded and projecting into the angle between the forks. 

 Sori roundish. Malay Peninsula. G.C. III. 28:435. 

 Hook. Fil. Exot., plate 97. 



5. Willinckii, Moore. Distinguished from P. grande 

 by the sori, which nearly fill the last forks but do not 

 approach the base of the sinus. The fronds are thinly 

 furnished with minute stellate hairs, at length glabrous 

 and pale green. Moore says : "fertile fronds in 3's, elon- 

 gate, pendent, with scarcely any disk, bipartite for about 

 two-thirds of their length, one of the margins of each 

 primary branch entire, the other bearing numerous lobes 

 in about three series on a dichotomous plan." Strong 

 features of this plant are the length, narrowness and 

 acuteness of the forks, and also the narrowness of the 

 "disk "or unbranched portion just below the primary 

 forks. Java. G.C. II. 3:303 (repeated in III. 10:701 and 

 28:431. A.G. 15:111. Gn. 10, p. 383 (repeated in Gn. 

 30, p. 300). 



6. -ffithidpicuni, Hook. (P. Stemmaria, Beauv.). Bar- 

 ren fronds rounded; fertile fronds 2-3 ft. long, clus- 

 tered, pendent, twice dichotomous (not twice trichot- 

 omous, as some writers say) : sorus a V-shaped patch 

 surrounding the sinus. Guinea, Angola. Hooker's 

 Garden Ferns, plate 9. A.G. 15:111. G.M. 40:135 (erro- 

 neously as P. grande). The fronds are said to be cov- 

 ered below with a thin cottony down. 



7. Hillii, Moore (P. alcicdrne, var. Hillii). Barren 

 fronds like P. alcicorne, but the fertile fronds are erect, 

 the unbranched portion longer, the forks more numer- 

 ous and compact, the segments shorter and more 

 acute. Fronds clustered thinly, covered when mature 

 with white stellate hairs: sori in oval or roundish 

 masses, not at the base of the sinus but near the base 

 of each of the last segments. The upper third of the 

 fertile frond is 15-18 in. across, 3-parted, the central 

 segment with 1 or 2 side lobes near the apex, the 2 lat- 

 eral segments broader and twice or thrice forked into 

 5-10 ultimate lobes." T. Moore. Queensland. G.C. II. 

 10:51, 428, 429. J.H. III. 32:497. 



8. alcic6rne, Desv. Barren fronds rounded, convex, 

 wavy margined; fertile fronds clustered, attaining 2-3 

 ft., 2-3 times dichotomous, the unforked portion erect, 

 the segments pendent, rather narrow and sharply cut, 

 under surface covered with thin cottony down: sori in 

 irregular masses, filling the last forks and a space 

 across their bases, shown in B.R. 3:262, 263 (as Acros- 

 ticJnim alcicorne). Temperate Australia. A.G. 14:153; 



