THEA. 



287 



THEBMOPSIS. 



the roots, according to their respective 

 kinds. 



Thalia. — Carina. — T. dealbata 

 is an aquatic plant, a native of South 

 Carolina, with very curious hlack and 

 white fragrant flowers. It is ahout as 

 hardy as Cdlla ethibpica, and re- 

 quires the same treatment. — See 

 Arum. 



Thauctrum. — Ranunculacece. — 

 Meadow Rue. Perennial plants, na- 

 tives of Europe and North America, 

 which are quite hardy in British gar- 

 dens. T. aquilegifolium and its 

 varieties are very showy border-flow- 

 ers ; and T. alpinum, and some other 

 dwarf species, are elegant plants for 

 rockwork. They all grow freely in 

 any common garden soil. 



Thatching is sometimes applied as 

 a protection to half-hardy trees in 

 the open ground. Many half-hardy 

 trees and shrubs may be protected 

 from any danger from frost by laying 

 straw over the roots and collar of the 

 stem, and then thatching it, as shown 

 in Fig. 35. 



Fig. 35. 



PROTECTING HALF-HARDY TREES BY 

 THATCHING. 



Thea. — Ternstrcemiaceee. — Ever- 

 green half-hardy shrubs, natives of 



China, and nearly allied to the Ca- 

 mellia, from which indeed they differ 

 only slightly in the capsule. They 

 are only half-hardy in British gardens. 

 TheaBohea, indeed, requires protec- 

 tion every winter ; but T. vzridis 

 will live in the open air with very 

 slight protection (such as laying straw, 

 &c, over the roots) in severe frosts. 

 The flowers of both kinds resemble 

 those of small single white Camellias ; 

 and they are cultivated more from the 

 curiosity which most persons feel to 

 see the plants producing tea, than 

 from any real beauty they possess. 



Theobro^ma. — Byttneriacece. — 

 The Chocolate-nut Tree. The tree 

 from the nuts of which cocoa and 

 chocolate are prepared, comes very ap- 

 propriately after the Tea Tree. There 

 are three species, all natives of South 

 America, with brownish flowers ; all 

 of which require a stove in England, 

 and should be grown in light rich 

 soil. 



Theophrasta .—Apocynece.— 'Stove 

 plants with very handsome leaves and 

 white flowers. They are grown in 

 loam and peat, and they are propa- 

 gated by cuttings. 



Thermometer. — No amateur 

 should attempt to grow plants in a 

 greenhouse or stove, or even in a hot- 

 bed, without being provided with a 

 thermometer to regulate the degree 

 of heat. A very ingenious one with 

 a long tube for plunging into the 

 ground has been contrived for ascer- 

 taining the heat of a hotbed or tan- 

 pit. 



Thermopsis. — ■ Leguminosce. — 

 Herbaceous plants with yellow flow- 

 ers, natives of Europe and North 

 America, which should be grown in 

 very rich soil, but which are quite 

 hardy in the open air in Britain. 

 There is one ligneous species, Ther- 

 mopsis laburnifblia, D. Don, (Ana- 

 gyris indica, Willd.,) but it is now 

 generally called Piptanthus nepa- 



