in; 



£f)c Srcastarg ai 3Sotanr>. 



[thtjj 



sionally replaced by tendrils. The sepals 

 and petals are four or five in number ; 

 stamens eight, inserted within a thick 

 disk, ovary three-lobed, with a single 

 ovule in each of its three compartments ; 

 fruit a three-winged samara. T.pinnata 

 is cultivated as a stove-plant in this coun- 

 try. The genus is named in honour of 

 3l" Thouin, Professor of Agriculture at 

 Paris. [31. T. M.] 



THREE-CLEFT, THREE-PARTED , Split 

 into three parts or divisions, deeper than 

 when three-lobed. 



THREE-EDGED. Having three . acute 

 angles with concave faces, as the stems of 

 many plants. 



THREE-LOBED. Divided into three 

 lobes or segments. 



TH REE-VALVE D. Applied to capsules 

 which open by three valves or divisions. 



THRELKELDIA. An Australian genus 

 of Chenopodiaceo?, comprising a smooth 

 branched undershrub, withalternate semi- 

 terete leaves, and solitary sessile axillary 

 flowers, which have an urceolate perigone 

 with three membranous scales within 

 the margin ; three stamens, opposite 

 the scales; and an utricle enclosed in the 

 enlarged fleshy perigone, with a single 

 vertical seed. [J. T. SJ 



THRIFT. Armeriavulgaris. —, PRICK- 

 LY. Acantholimon. 



THRLXAX. A small and principally 

 West Indian genus of Fan Palms (Palma- 

 cece), distinguished from its congeners by 

 its flowers having a deeply six-cut calyx ; 

 no corolla; six nine or twelve stamens 

 joined together at the bottom ; and a 

 simple ovary containing a single erect 

 ovule, and terminated by a hollow one- 

 sided funnel-shaped stigma. Six or eight 

 species are known, all comparatively low- 

 growing palms, seldom exceeding twenty 

 feet in height, and frequently not more 

 than ten; having their trunks clothed with 

 the persistent bases of old leaves or mark- 

 ed with circular scars, and bearing a crown 

 of much-cut fan-shaped leaves. Their 

 flower-spikes grow from the axils of the 

 leaves, and have their stalks sheathed with 

 numerous spathes ; the flowers being of a 

 greenish or greenish-yellow colour, and 

 producing little round one-seeded fruits. 



In Jamaica these palms are commonly 

 known by the name of Thatch-palms, from 

 their leaves being used for thatching, for 

 which some of them are admirably adapted. 

 One of them, T.argentea, the Silver Thatch- 

 palm, is usually said to yield the young 

 unexpanded palm-leaves imported from 

 the West Indies under the name of Pal- 

 metto Thatch, and extensively employed 

 for making palm-chip hats, baskets, and 

 other fancy articles ; but it is more than 

 probable that the leaves are gathered from 

 several species, while in the United States 

 those of the allied genus Sabal are substi- 

 tuted. The tough leafstalks are also split 

 into strips and woven into serviceable 



I baskets, and the undeveloped leaves or 

 | cabbage forms an excellent vegetable. T. 

 argentea is likewise a native of Panama, 

 where it is called Palma de escoba, or 

 Broom-palm, its leaves being there made 

 into brooms. [A. S.] 



THRINCIA. A genus of stemless her- 

 baceous plants, with rough leaves, and 

 solitary yellow flowers, belonging to the 

 tribe Cichoracece of compound flowers. The 

 characters are -.—Involucre unequally im- 

 bricated ; pappus of the outer florets short 

 and scaly, of the inner plumose ; receptacle 

 naked. T. hirta, the only British species, 

 is a common plant on gravelly pastures 

 and commons, sending out from the crown 

 of the root a few horizontal or ascending 

 lanceolate often runcinate leaves, and 



| slender scapes bearing each a solitary yel- 

 low flower. The fruit of the inner florets 



i is beautifully striated and marked with 



J raised dots. The foreign species possess 

 no attractive properties which render them 



. worthy of cultivation. [C. A. J.] 



THROAT. The orifice of amonopetalous 

 flower. 



THROATWORT. TracheUum; also Cam- 

 panula Ceruicaria and Digitalis purpurea. 

 — .GREAT. Campanula 'JQraeiielium. 



| THRTJMWORT. Actinocarpus ; also 

 j Amaranthus caudatus. 



\ THRYALLTS. A genus of Malpighiacece, 

 ! consisting of Brazilian climbing shrubs, 

 whose young branches and inflorescence 

 are covered with star-shaped hairs. The 

 calyx is five-parted, without glands; the 

 corolla yellow, of five stalked petals ; sta- 

 mens ten, all fertile, the filaments united 

 at the base; ovary three-celled; styles 

 three ; fruit surrounded by the enlarged 

 calyx, and consisting of three indehiscent 

 carpels. One or two species are in culti- 

 vation as stove-climbing plants. [M. T. MJ 

 I THRYPT03IENE. The name of a shrub 

 belonging to the Cliamalauciacew, and 

 native of South-western Australia. The 

 leaves are somewhat cylindrical, spine- 

 pointed ; and the flower-stalks axillary soli- 

 tary, one-flowered, shorter than the leaves. 

 The calyx-tube is marked with ten ridges, 

 j its limb divided into five petaloid seg- 

 i ments; petals five, stamens ten, all fer- 

 ! tile, the anthers roundish, with a small 

 terminal gland , ovary one-celled, with one 

 or two ovules , fruit capsular. [31. T. MJ 



THUJA. (Ft?) Thuja orientalis. — THE- 

 RIACAL. Thuja occidentahs. 



THUJA. The derivation of this name is 

 said to be from thyon ' sacrifice,' the resin 

 of some of these plants having been used 

 instead of incense The genus is included 

 In the cupressineous division of Coniferce, 

 and consists of evergreen trees natives of 

 North America. One species is very com- 

 mon in English gardens under thename of 

 Arbor A 7 itEe, the origin of which designa- 

 tion is uncertain. The branches are very 

 numerous, the smaller ones arranged in 

 two rows, and covered wi,th small closely- 



