1192 



PALAUA 



PALM 



solitary; calyx 5-cut: ovary many-celled; style stigma- 

 tose at the apex; carpels crowded without order. 



flexuosa, Mast. Slender, branched from roots : stems 

 8-10 in. long, ascending, flexuous above : leaf-stalks 1-2 

 in. long; blades 1-2 in. long and broad, triangular in out- 

 line, pinnatifld, the segments lobed; lobes obtuse: fls. 

 mauve, paler towards center, with bright red anthers 

 which are very numerous and arranged in 5 longitudinal 

 series; styles 25-30. Peru. B.M. 5768. 



PALAVA. See Palaua. 



PALltTKUS (ancient Greek name). Rhamndcece. 

 Spiny trees or shrubs with alternate, 2-ranked, 3-nerved 

 Ivs., small greenish yellow fls. in axillary clusters and 

 orbicular broadly winged, curiously shaped fruits resem- 

 bling ahead with a broad-brimmed hat. The one species 

 cultivated in this country is not reliably hardy north of 

 Washington, D. C.; in Mass, it is killed every winter 

 almost to the ground even with protection, and the young 

 shoots flower but bear no fruit. It is'not very ornamental, 

 but the dark green foliage is pretty and the curious fruits 

 are interesting. It thrives in any well-drained soil and 

 prefers a sunny and warm position. Prop, by seeds 

 stratified or sown in autumn and by layers or root-cut- 

 tings. Four species from S. Europe to China and Japan. 

 Stipules usually changed into spines : fls. small, perfect, 

 in axillary or sometimes terminal cymes; petals 5, 2- 

 lobed; stamens 5: fr. woody, 3-celled, depressed sub- 

 globose, with a broad, orbicular, horizontal wing; cells 

 1-seeded. 



Spina-Christi, Mill. (P. austrdlis, Gertn. P. aculea- 

 tus, Desf. Zisyphus Paliurus, Willd. Rhdmnus Pali- 

 urus, Linn.). JERUSALEM THORN. CHRIST'S THORN. 

 Spreading, spiny shrub to 10 ft., sometimes procumbent: 

 1 of the 2 spines at the base of the petioles straight, the 

 other hooked and recurved: Ivs. rather slender-petioled, 

 ovate, usually unequal at the rounded base, obtuse, mi- 

 nutely serrulate, glabrous, dark green above, pale or 

 grayish beneath, %-!% in. long: fls. in axillary short- 

 peduncled cymes: fr. brownish yellow, about % in. 

 across, glabrous. June, July. S. Eur. to Himal. and N. 

 China. B.M. 1893 (as Zizyphus Paliurus) and 2535 (as 

 P. virgatus). This plant is supposed to have furnished 

 the crown of thorns which was placed on the head of 

 Christ before his crucifixion; others believe Zizyphus 

 Spina-Christi to be the shrub the crown was made of. 

 These two shrubs resemble each other so closely that 

 they hardly can be distinguished without frs. which are 

 berry-like in Zizyphus ; the shape of the thorns is ex- 

 actly the same in each species. 



P. orientalis, Hemsl. Tree, to 30 ft.: Ivs. 2-4 in. long, gla- 

 brous: fr. 1-1 j-2 in. across, glabrous, purplish. China. This 

 but recently introduced species is perhaps the most ornamental 

 of the genus ; it has- not proved hardy at the Arnold Arbor- 

 etum. P. ramosissimus, Poir. (P. Aubletia, Roem. & Schult,). 

 Shrub similar to P. Spina-Christi, but with both spines straight, 

 larger Ivs. pubescent beneath, and smaller tonlentose frs. 

 China, Japan. ALFRED REHDER. 



PALM. Plate XXIV. Palms are amongst the most 

 striking plants in tropical floras. Their tall, straight, 

 unbranched trunks surmounted by a spreading canopy 

 of huge pinnate or digitate foliage distinguish them 

 from nearly all other forms of vegetation. They are 

 widely spread in tropical regions, being most abundant 

 in America and few in Africa. They are particularly 

 conspicuous in the Pacific islands. Although the Palms 

 are such bold and interesting plants, the species are 

 very imperfectly understood. This is due to the great 

 difficulty of making herbarium specimens, to the fact 

 that the greater number of botanists are residents of 

 regions in which Palms do not grow, and to the differ 

 ences of opinion as to the relative importance of the 

 various botanical characters. Many of the Palms have 

 been named first from cultivated specimens, and often 

 before the flowers and fruits are known. When the 

 specimens finally come to fruit, the names are usually 

 shifted, causing much confusion. The proper generic 

 position of a Palm may be unknown for several years 

 after it becomes popular in the horticultural trade. 

 Consider the changes in nomenclature which have 

 occurred in Palms that have been referred to the 

 genera Areca and Kentia. 



The species of Palms are not very numerous. They 

 probably do not exceed 1,000, although more than that 

 number have been described. Bentham & Hookes accept 

 132 genera, and Drude, in Engler & Prantl's "Pflanzen- 

 familien," accept 128 genera. Most of the genera are 

 small, and many of them are monotypic. The largest 

 genera are Calamus, with about 200 species, all Old 

 World, mostly Asian; Geonoma, with about 100 species, 

 all American; Bactris, about 100, American; Chamse- 

 dorea, with about GO, all American; Licuala, with 30, 

 ranging from eastern Asia to Australia; Desmoncus, 

 about 25, American ; Cocos, 30, all confined to America but 

 the cocoanut, which is now cosmopolitan ; Pinanga, with 

 about 25 species, of the Oriental tropics; Areca, nearly 

 two dozen, Oriental. Many of the species, particularly 

 in the small genera, are restricted to very small geo- 

 graphical regions, often to one island or to a -group of 

 islands. The Palms represent an old type of vegeta- 

 tion, and they are now, no doubt, on the decline. 



Palms have been favorite greenhouse subjects from 

 the period of the first development of the glass plant- 

 house. The stereotyped form of conservatory is a 

 broad or nearly square structure, with narrow benches 

 around the sides over the heating pipes and a Palm bed 

 in the center. In these conservatories a variety of 

 Palms will succeed, requiring neither a very high tem- 

 perature nor much direct simlight. In fact, Palms usu- 

 ally succeed best under shaded roofs. The Palms are 

 most satisfactory in their young state, before the trunks 

 become very prominent, and before the crowns reach 

 the glass. The larger number of Palms have pinnate or 

 pinnatisect leaves, and these species are usually the 

 more graceful in habit. Small Palms are now in great 

 demand for room and table decoration, and a few spe- 

 cies are grown in enormous qviantities for this trade. 

 They are sold when small. They usually perish before 

 they are large enough to be cumbersome. Amongst the 

 most popular of these Palms are Chrysalidocarpus 

 lutescens, Howea Belmoreana and Forsteriana, Cocos 

 Weddelliana, Livistona Chinensis, and possibly one or 

 two species of Phoenix. 



Some Palms endure considerable frost without injury. 

 Of such are the Sabals and the Palmettoes of the south- 

 ern states. The Saw Palmetto (Serenoa serrulata) and 

 the Blue Palmetto (Rhapidophylhim Hystrix) occur as 

 far north as South Carolina. In Asia, Nannorhops grows 

 naturally as far north as 34, and in Europe, Chamse- 

 rops (the only Palm indigenous to Europe) reaches 44. 



In the tropics, Palms furnish houses, clothing, food 

 and ornaments. The range of the economic uses is well 

 indicated by the following extract from Drude ( in Engler 

 & Prantl): In a family which, like the Palms, is of 

 such extraordinary importance in satisfying so many 

 human wants, it seems well to make a few general re- 

 marks on this subject as an introduction to special re- 

 marks under the different \genjera^~^&. European does 

 well to distinguish between rneproducte of the Palms 

 which are imported from the tropics, and those which 

 are used by the civilized peoples and more especially by 

 the natives in the tropics. Of the first, there should be 

 noted a few fruits, as, for example, dates and cocoanuts, 

 whose use gives us a slight picture of the importance of 

 Palm fruit of the tropics. Then follows the Indian sago 

 coming from the pith of the stems, which surpasses in 

 quality the European product, and then the oil made 

 from fruits of oil Palms which, considering its almost 

 unlimited supply, is of more importance than the olive 

 oil. In Europe a great role is played by the fibers com- 

 ing from many Palms, as the Piacaba and Cocoa fibers. 

 Perhaps, in the course of time, one or other of the 

 Palm-leaf products will find greater use in the produc- 

 tion of paper. The numerous kinds of 'Spanishschen 

 Rohres,' that is, those thin stems of the genus Calamus 

 which have a silicious covering, are necessary in the 

 making of bent-wood furniture and baskets. Wax (from 

 Copernicia, probably not from Ceroxylon) plays in 

 Europe, as a competitor of beeswax, but a small role. 

 On the other hand, the stone nuts, seeds of Phytelephas 

 and the stony kernels of some Cocoineae, are imported 

 from America in ton quantities, to be used in making 

 small articles. To these products, of considerable 

 influence on the European trade, must be added num- 

 berless others used in the tropics, where the numerous 



