PERIPLOCA 



the anthers couneeted at the apex aiul villous; style 

 shoit. with broad stigma: fr. cousistiug of 2 follicles, 

 coiitaiuiiig uumerous, small, winged seeds. 



Graeca, Linn. Silk Vine. Deciduous shrub, twining 

 to 40 ft. : Ivs. petioled, ovate to oblong-lanceolate, 

 acuminate, dark greeu and glossy above, 2-t in. long: 

 fls. in loose, long-peduncled cymes, brownish purple 

 inside, greenish at the margin and outside, %-l in. 

 across; petals oblong, villous; crown with 5 slender 

 thread-like incurved glabrous appendages : follicles 

 narrow, about 4 in. long. July, Aug. S. Eu., W. Asia. 

 B.M. 2289. B.R. 10:803. L.B.C. 14:1389. Gn. 34, p. 78. 

 — Under the name of P. atigustifoUa a narrow-leaved 

 form is sometimes cultivated, but it is P. Grwca, var. 

 angnstifolia, Jiig. The true P. angustifolla , Labill., is 

 synonymous to P. Icevigata, Ait., from the Canary Isl. 

 and N. Africa, with persistent Ivs. and pubescent ap- 

 pendages of the crown. Alfred Rehder. 



PEEISTfiEIA (Greek, dove, from the form of the 

 column aud wings). OrchidAcete. A genus of stately 

 South American orchids, having large plicate leaves 

 unfolding successively, and tall, erect or hanging 

 flower-spikes. The flowers are nearly globose or cup- 

 shaped, of a waxy texture, with broad, concave seg- 

 ments. The genus is distinguished from the related 

 genera Acineta, Sacsena, Gongora, etc., by the curious 

 shape of the labellum and column. The base of the 

 lahi'llum (hypochil) is united with the column by broad 

 winiis (pleuridia). The upper part of the labellum 

 (t'pichil) is movably joined to the hypochil. Five 

 species, of which two are commonly cultivated. 



These plants are easily kept alive, but difficult to 

 flower. When growth begins they should be planted in 

 well-drained compost of fibrous loam, leaf-mold and 

 sand, and carefully watered until the plants become 

 vigorous. Later liquid manure or bone-dust may be 

 given them in order to obtain large and vigorous flower- 

 spikes. Liberal treatment will produce flne specimens, 

 Ixit poorly fed plants often fail to flower at all. When 

 resting, they should be removed from the tropical 

 Iiouse to a cooler room. P. elata is often grown as a 

 ]iiuely terrestrial orchid. 



elita. Hook. Dove Flower. Holt Ghost Flower. 

 Fig. 1722. Pseudobulbs 4-5 in. high, bearing several 

 strongly veined Ivs. 2-3 ft. high: fl.-stem 3-4 ft. high; 

 fls. in a raceme covering about one-third the length of 

 the flower-stalk, cup-shaped, creamy white, wax-like and 

 fragrant, 2 in. across ; sepals broadly ovate to rotund ; 

 I)etals more delicate; labellum fleshy, broadly obovate, 

 truncate, sprinkled with deep purple; column with large, 

 curious wings, supposed to bear resemblance to a dove, 

 June-Sept. Panama. B.M. 3116. Gng. 5:151. V. 8:103. 

 Gn. 12, p. 1.53; 30, p. 574; 42, p. 324. R.H. 187C, p. 133; 

 1877:110. — The labellum and wings of the column are 

 sometimes spotted with purple. 



p^ndula, Hook. Pseudobulbs ovate-oblong, 4-5 in. 

 high, bearing lanceolate, strongly veined Ivs.: scape 

 pendulous, from the base of the pseudobulb, bearing as 

 many as 20 fls.: fls. globular in outline, 1% in. across, 

 fragrant, greenish white outside, tinged with rose and 

 thickly dotted with purple within; sepals roundish con- 

 cave, united at base; petals rather smaller; labellum 

 fleshv, curiously shaped, enclosed within the flower. 

 Guiaiia. B.M. 3479. G.C. IL 25:116. -Requires tropical 

 treatment, but rarely flowers in cult. 



P. Humboldtii, Liiidl.=Aeineta Humboldtli, Lindl. 



Heinrioh Hasselbring. 



PEEISTEOPHE (Greek, peri, around, and strophos, 

 belt; alluding to the involucre). AcanthAceai. Erect 

 branched or loosely creeping herbs or half-shrubby 

 greenhouse plants cult, for their flowers. Lvs. entire: 

 fls. solitary or in clusters of 2-3 surrounded by an 

 involucre, in loose cymes or cymose panicles, or distant 

 on slender branches; bracts of the involucre narrow; 

 calyx deeply 5-parted, shorter than the bracts, scariose 

 or hyaline; corolla-tube long, slender, slightly enlarged 

 above, limb deeply bilabiate, the posterior lip narrow, 

 erect, concave, entire or emarginate, lower lip spread- 

 ing, apex 3-parted ; stamens 2, a little shorter than the 

 corolla lips; anthers 2-celled; sterile stamens none; 



81 



PERNETTYA 



1279 



style filiform: cap.sule oblong-, contracted into a solid 

 stalk. About 15 species, rang:ing from tropical Africa 

 through the Malay Islands and Australia to India. 



The plants are cult, like Jacobinias or Justicias, of 

 the same family. Cuttings taken at any time when the 

 wood is soft will root in a warm bed in 3— i weeks, after 

 which the potted plants may be removed to a house of 

 lower temperature. They require a rich loam mixed 

 with some leaf -mold, aud plenty of air. 



1723, Peristrophe speciosa iX 14)- 



specidsa, Nees (Justlcia sj^ectosa, Roxb.). Fig. 1723. 

 Plants erect, spreading and branched, becoming 2-3 ft. 

 high: Its. opposite, petioled, ovate-acuminate, smooth: 

 fls. in clusters of 2-3 on slender branches, violet-purple, 

 \% in. long. Fls. for a long period in winter. India. 

 B.M. 2722. L.B.C. 20:1915. B. 2:74. -A pot-plant of 

 bu.shy, compact habit when well grown. Good for the 

 window. Usually thrives best in partial shade. 



angnstifdlia, Nees. Plants low, erect, very much 

 branched : branches nearly horizontal, pubescent above: 

 lvs. lanceolate, pointed at both ends: fls. sparse, in ter- 

 minal cymes, rose-colored. Flowers freely. Java. —A 

 var. ailrea variegfi.ta has the center of the lvs. varie- 

 gated with yellow. Useful for vases and baskets. 



Heinkich Hasselbring. 



PERIWINKLE. Vinca. 



PERNETTYA (after A. J. Pemetty (1716-1801); ha 

 accompanied Bougainville on his voyage and wrote "A 

 Voyage to the Falkland Islands ") , EHcAcece. Ornamen- 

 tal low evergreen shrubs, with small, alternate, usually 

 serrate lvs. and small, white or pinkish, nodding fls., 

 usually solitary in the axils and followed by very deco- 

 rative berries varying in color from white to purplish 

 black or bluish black and remaining on the branches 

 all winter. These exceedingly pretty shrubs are great 

 favorites in England, but are little known in this coun- 

 try. P. miicrouata and P. angnstifolia^ the hardiest, are 

 probably hardy in sheltered positions as far north as 

 New York. They are well suited for rockeries and bor- 

 ders of evergreen shrubberies and also make very hand- 

 some pot-plants. They grow best in a peaty and porous 

 moderately moist soil and prefer sunny positions, but 

 seem to grow almost as well in any other well-drained 

 soil; in shade they will not fruit as profusely as in the 

 full sun. Prop, by seeds or by cuttings of half-ripened 



