1338 



PILOCEREUS 



7. Houllecii, Lem. Tree-like, attaining 40 ft. in height : 

 branches divaricate ; cultivated plants usually 3-4 in. in 

 diam: ribs 6-8, rounded, glaucous ; radial spines 7-9, 

 spreading K in. long, honey yellow, central twice as 

 long and stronger: areolse of the sterile stem with more 

 or less hairs, which in the fruiting area are very numer- 

 ous, making a shaggy tract sometimes 1 ft. long: fls. 3 

 in. long, imbedded in the wool, turbinate, greenish red 

 outside, rose-red within: fr.dark red, depressed-globose. 

 Mexico. R.H. 1862, pp. 427-430. 



AAA. Fruiting area a prominent cephalium composed of 

 dense locks of woolly hairs intermixed with 

 bristles, unilateral except sometimes in P. 

 chrysomallus. 

 B. Long hairs absent except in the cephalium. 



8. Columna-Trajani, Salm-Dyck. Tree-like, attaining 

 a height of 50 ft. and a diam. of over 2 ft., simple below: 



areolse large, elliptic ; radial 

 spines 10-12, the upper very 

 short, the lower longest, nearly 

 an inch long ; centrals 2, the 

 upper an inch long, the lower 

 4-5 in.: fls. about 2 in. long, 

 scarcely projecting from the 

 unilateral woolly and bristly 

 cephalium. Mex. R.H. 1890, p. 

 129. The specific name refers to 

 the famous Trajan's Column. 



BB. Long hairs covering all but 

 the oldest parts of the 

 plant. 



9. chrysomallus, Lem. Tree- 

 like, with erect branches, reach- 

 ing a height of 30 ft. : ribs in 

 cultivated plants 13 : areolae 

 with long hairs ; radial spines 

 11-13, the upper % in. long, the 

 lower twice as long; centrals 4, 

 still longer; all the spines am- 

 ber-yellow, becoming brown : 

 cephalium terminal or some- 

 times unilateral, a foot long, 

 woolly and setose. Mex. 



10. senllis, Pfeiff. OLD MAN 

 CACTUS. Columnar, reaching a 

 height of 35 ft. and a diam. of 

 1 ft., branching at the very 

 base, the branches becoming 

 parallel with the parent: ribs 

 20-30, very little elevated ; areolse 

 bearing 20 to 30 white, wavy 

 bristles 2-5 in. long; later ap- 

 pear also, at first 1, then 3-5 

 strong, yellowish spines : fls. 

 very numerous in the cephal- 

 ium, nearly 4 in. long, red out- 

 side, reddish white within: fr. 



Central Mex. R.H. 1889, p. 568; 1890, 



Pilocereus Schottii. 



violet, 2 in. long, 

 p. 128. 



11. Dautwiztii, Haage (P. Hadgei, Poselg.). Colum- 

 nar, reaching 5 ft. in height, 4 in. in diam. : ribs 25-30, 

 low, obtuse : areolse close together, bearing over 20 

 needle-like, spreading and interlocking spines, and also 

 copious long, white, curled hairs which cover the whole 

 upper part of the plant, like a spider's web: cephalium 

 and fl. not certainly known. Northern Peru. G.C. 1873:7. 

 F.S. 21:2163. 



AAAA. Fruiting areolce and younger parts of the plant 

 bearing short hairs, but cephalium wanting. 



12. exerens, Schum. (P. vlrens, Lem.). Branching at 

 base, 3-4 ft. high, 2-3 in. in diam., tapering above: 

 ribs 4-6, obtuse, the sterile shoots with short, sparse, 

 woolly hairs at the top; spines commonly 7 radials, 

 very short, 1-3 centrals 4 times as long; woolly hairs 

 much more abundant on the blooming plant: fls. about 

 3 in. long, trumpet-bell-shaped, without wool or spines. 

 Brazil. KATHARINE BRANDEGEE. 



PILOGYNE. See Melothria. 



PIMELEA 



PILtMNA. See Trichopilia. 



PIMELEA (Greek, fat; referring to the fleshy seeds). 

 Thymelceacece. RICE FLOWER. A genus comprising 

 many showy species, and confined almost exclusively 

 to Australia and neighboring islands. They are mostly 

 delicate shrubs, fitted only for greenhouse culture, 

 though reported to be hardy in the open wherever the 

 lemon can be successfully grown. Lvs. nearly always 

 opposite, always simple and entire: inflorescence usii- 

 ally a terminal head or cluster, never umbellate, often 

 with an involucre of 4 or more bracts at the base : per- 

 ianth tubular, with a spreading (rarely erect) 4-lobed 

 limb: stamens 2, inserted in the throat opposite the 2 

 outer perianth-lobes : ovary 1-celled : fr. a small drupe. 

 Of the many species, only three (P. decussata, P. li- 

 gustrina and P. spectabilis) have been actually intro- 

 duced into the U. S., but there are so many other very 

 showy species, some of which are already in the Old 

 World, that in all probability more will soon be found 

 in our collections for greenhouse culture. For the lat- 

 ter the soil should be a mixture of peat and loam, with 

 enough sharp sand added to make it "gritty," and spe- 

 cial care given to insure perfect drainage. After bloom- 

 ing, the plants should be cut back severely to stimulate 

 new growth. They can be propagated from either seeds 

 or cuttings. Ernest Braunton writes: "P. decussata 

 is an elegant little shrub, of uncertain existence. In 

 southern Calif, it attains a height of 3 ft., with the 

 same width at the top, flowers magnificently and then 

 dies. In northern Calif, it does the same. In the open 

 ground it lives 3-5 years, and must have shade." 



ARNOLD V. STUBENRAUCH. 



Cuttings of well-ripened wood of P. spectabilis and 

 P. decussata root freely at 60 placed under a bell-glass, 

 in a shaded house. They are not strong growers and 

 must not be over-potted. During the summer they do 

 best when plunged outside but covered with lath racks. 

 They may be kept with auriculas. During the winter 

 they may be kept with ericas at 40-45 at night, and they 

 will come in at Easter without forcing. They are rather 

 slow-growing plants for a commercial man, but they 

 probably will become profitable. P. decussata, espe- 

 cially, is one of the finest of pink greenhouse shrubs. 



H. D. DARLINGTON. 



The following are all natives of Australia, except 

 when otherwise stated : 



arenaria, 9. 

 decussata, 13. 

 drupacea, 2. 

 ferruginea, 13. 

 glauca, 6. 

 graciliflora, 8. 



INDEX. 



hypericina, 3. 

 imbricata, 16. 

 ligustrina, 4. 

 linifolia, 7. 

 longiflora, 1. 

 nivea, 12. 



rosea, 10. 

 spathulata, 15. 

 speetabilis, 14. 

 suaveolens, 5. 

 sylvestris, 11. 



A. Involucral Ivs. absent 1. 



AA. Involucral Ivs. reduced to 2 small 



bracts 2. 



AAA. Involucral Ivs. 4-8. 



B. Lvs. distinctly penniveined. 



c. Fls. white 3. 



4. 



cc. Fls. rose-colored or yellowish. 5. 

 BB. Lvs. not penniveined or very 



obscurely so. 



C. Color of involucral Ivs. green. 

 D. Fls. white. 



E. Perianth - tube cylindri- 

 cal 6. 



7. 

 EE. Perianth-tube wider at 



longiflora 

 drupacea 



hypericina 

 ligustrina 

 suaveolens 



top. 



EEE. Perianth-tube narrower 



at top 9. 



DD. Fls. rose-colored. 



E. Perianth-tube cylindri- 

 cal 10. 



BE. Perianth-tube ivider at 



top 11. 



DDD. Fls. white and pink in 



same head 12. 



glauca 

 linifolia 



graciliflora 

 arenaria 



rosea 



sylvestris 



nivea 



