THLADIAXTHA 



THRIXAX 



3333 



dubia, Bunge. A tall climber: Ivs. light green, oval, 

 base cordate, apex acute: fls. numerous, yellow, bell- 

 shaped; male fls. solitary in the axils without bracts: fr. 

 ovoid-oblong, about 2 in. long, red; seeds black, smooth. 

 Summer. N.China. G.C. III. 28:279; 54:54. B.M. 

 5469 (male fl. only). G.M. 43:657. According to R. 

 I. Lynch, in Gn. 56, p. 518, the plants are of easy cult, 

 and by planting both sexes and artificial pollination the 

 fr. may be grown. He further states that the root-tubers 

 are without buds but form buds just before growth com- 

 mences, as does a root-cutting. According to Danske 

 Dandridge, the plant is hardy in W. Va., increasing 

 rapidly by tubers and becoming a pest when planted 

 with choicer plants. 



Oliveri, Cogn. More vigorous than the former: 

 annual sts. attaining a height of 30 ft. or more, glabres- 

 cent, tubers absent: Ivs. larger, cordate, acute, about 8 

 in. long: fls. more numerous, golden yellow. Cent. 

 China. R.H. 1903, p. 473. There is also a hybrid 

 between these two species which is offered in the trade. 



F. TRACT HUBBARD.| 



THLASPI (Greek, crushed, referring to the strongly 

 flattened pods and seeds). Crueiferse. Annual or 

 perennial herbs which are glabrous or glaucous, rarely 

 pilose, some of which are cultivated now and then. 



Leaves basal, rosulate, entire or dentate; cauline 

 oblong, hastate-auriculate: fls. racemose, without 

 bracts, white, rose, or pale purple; sepals erect, equal 

 at base; petals obovate; stamens free, without append- 

 ages: silique short, laterally compressed, oblong, obcor- 

 date or obcuneate. About 90 species, widely dis- 

 tributed in the temperate, alpine, and arctic regions, 

 mostly in the northern hemisphere, but also in S. Amer., 

 S. Air., and Austral. 



alpestre, Linn. Perennial, 2-12 in. high but usually 

 low, glabrous, somewhat glaucous, habit tufted, form- 

 ing rather thick mats: basal Ivs. in a rosette, petioled, 

 obovate; cauline Ivs. elongated-lanceolate, base cor- 

 date, entire or dentate: peduncle unbranched, terete: 

 fls. white, sometimes somewhat reddish; sepals purplish. 

 Alpine Eu. Has been offered as a neat little rock- 

 plant. It should be given shade and a cool moist soil. 

 The material growing in Colo, and formerly called T. 

 alpestre is now considered a distinct species, T. colora- 

 dense, Rydb. Perennial, cespitose: basal Ivs. rosulate, 

 broadly spatula te, sinuately crenate or subentire; 

 cauline Ivs. oblong or obovate, obtuse: infl. short and 

 dense; fls. white; sepals with a white margin. Moun- 

 tains of Wyo. and Colo. The fls. are larger than those 

 of T. alpestre and the pod differs. It is uncertain 

 whether the material in cult, in Amer. is this plant or 

 T. alpestre. 



arvense, Linn. PEXXY CRESS. Annual or biennial, 

 6-18 in. high, glabrous, yellow-green: basal Ivs. obovate 

 or spatulate, petioled; upper Ivs. oblong, remotely and 

 irregularly dentate: fl.-st. mostly branched above: fls. 

 small, white; sepals greenish. Eu. A weed in most 

 countries, including Amer. 



T. btUidifblium, Griseb. Perennial, dwarf, cespitose: basal Ivs. 

 oblong-spatulate; cauline Ivs. few, oblong, very short auriculate: 

 fls. violet. Mountains of S. E. Eu. and Caucasus. T. rotundifdlium, 

 Gaudin. Perennial, 2-6 in. nigh: sts. numerous, ascending: basal Ivs. 

 rotundate-ovate, petioled; cauline Ivs. clasping, auricled: fls. violet, 

 rarely white. Switzerland. G.C. III. 49:116. 



F. TRACT HUBBARD. 



THORN: Cratsgus. Christ's T.: Paliunu Spina-Christi. 

 Jerusalem T.: Paliurus Spina-Christi; also Parkinsonia acuteata. 

 Swallow T.: Hippophae rhamnoides. 



THORN-APPLE: Datura Stramonium; also Crategus- 

 THRIFT: Armeria, Statice, 



THRINAX (Greek, fan). Palmacese, tribe Cdryphese. 

 THATCH PALM. Fan palms well adapted for pot culture. 



Spineless palms: trunks low or medium, solitary or 

 cespitose, ringed below, clothed above by the fringed 



If .-sheaths: Ivs. terminal, orbicular or truncate at the 

 base, flabellately plicate, multifid; segms. induplicate, 

 bifid; rachis short or none; ligule free, erect, concave; 

 petiole slender, biconvex, smooth on the margins; 

 sheath usually beautifully fringed: spadices long; axis 

 clothed with tubular sheaths, papery-coriaceous, split: 

 fls. perfect, the calyx and corolla united into a lobed or 

 entire cup, on rather long, slender pedicels, the pedicel 

 with a caducous bract at the base; stamens 6, their 

 filaments united below; ovary 1-celled: fr. the size of a 

 pea. About 17 species, native to W. Indies and Fla., 

 and not much known in cult. For the new Porto 

 Rican species, see Cook, Bull. Torr. Bot. Club, Oct., 

 1901 (vol. 28). Upon a technical embryo character 

 some of the species below and many other wild species 

 are segregated to constitute the genus Coccothrinax, 

 Sargent. As that genus does not differ horticulturally, 

 these species are here treated with Thrinax. See Cocco- 

 thrinax. 



The species are of slow growth, but succeed with 

 indifferent care. They are mostly of elegant form and 

 habit. A good specimen is shown in Fig. 3794. 



3794. A good specimen of Thrinax. 



A. Under surface of Ivs. green. 

 B. Ligule irith a blunt appendage at the middle. 

 radiata, Lodd. (Coccothnnax radiata, Schum. T. ele- 

 gans, Hort.). Caudex short: Ivs. green, glabrous or 

 slightly puberulent beneath ; segms. united to or beyond 

 one-third; ligule broadly rounded, with a short, blunt 

 appendage at the middle: spadix large, 2-2 Y^ ft. long, 

 paniculate. Cuba to Trinidad. Said to have been 

 known in cult, as T. elegans and T. gracilis. 



BB. Ligule bluntly deltoid. 



parvifldra, Swartz. Caudex 10-20 ft, tall: Ivs. 10-25 

 in. long, minutely pubescent, becoming glabrous, green 

 beneath; segms. united one-fourth or one-sixth their 

 length; ligule bluntly deltoid, \}/% lines long. Jamaica. 

 The plant of Fla. heretofore known as T. parviflora 

 seems to be T.floriddna, Sarg., a plant not in the trade. 

 S.S. 10:510. 



BBB. Ligule obsolete, truncate. 



barbadensis, Lodd. (Coccothnnax barbadensis, Becc.). 

 Trunk middle-sized: Ivs. green, glabrous; segms. united 

 at the base; ligule obsolete, truncate: spadix panicu- 

 late: berry polished, J^in. thick. Barbados. 



