THUj] 



&l)e Erca^ury af 33otanjj. 



1148 



pressed lozenge-shaped leaves arranged in 

 four ranks. Students are apt to mistake 

 the small branches and consider them as 

 leaves, by overlooking the minute closely- 

 pressed true leaves. The male flowers are 

 borne in small ovoid lateral catkins ; the 

 stamens themselves are in four rows, the 

 anther-scales having on their under-sur- 

 face four pollen-sacs bursting lengthwise. 

 The female cones, borne on the same plant 

 as the male ones, are solitary and terminal ; 

 each consists of eight to twelve oppo- 

 site woody scales, mucronate at the apex— 

 the outer ones with two winged seeds, the 

 inner ones sterile, 



T. occidentalis is the American Arbor 

 Vita?, a hardy evergreen shrub, which 

 thrives well in almost any situation. The 

 plant is everywhere pervaded by a po werf ul 

 aromatic odour, and the leaves have been 

 used as a remedy for rheumatism, on ac- 

 count of their sudorific properties. In 

 America the wood of the tree, which there 

 attains a much greater height than with 

 us, is used for posts and other similar 

 purposes. T. orientalis, the Chinese Arbor 

 Vita?, is sometimes put into a distinct 

 genus on account of its roundish cones, 

 more numerous scales, and wingless seeds 

 [see Biota]. It is a native of Japan and 

 China, and has long been cultivated in this 

 country. It is of a closer habit, has its 

 branches directed more vertically upwards, 

 and its leaves are smaller and more dense- 

 ly packed than in the American species. 

 This plant has a pungent aromatic odour; 

 the young branches are said to be used 

 for a yellow dye, and the wood is made use 

 of where something is required to with- 

 stand humidity. [M. T. M.] 



THUJ.ECARPUS. Juniperus. 



THUJOPSIS. A genus of cupressineous 

 C'raifercp, consisting of Japanese trees, 

 with whorled pendentbranches, the smaller 

 twigs being very numerous and two-rank- 

 ed. The leaves are opposite, overlapping, 

 or sickle-shaped and sharply pointed. The 



Thujopsis dola'orata. 



flowers are monoecious . the males in soli- 

 tary cylindrical catkins, with anther-scales 

 having three to five pollen-sacs on their 



under-surface ; and the females succeeded 

 by terminal cones, which are somewha 

 globular when ripe, the scales woody im- 

 bricated and five-seeded, the seeds being 

 winged. T. dolabrata, a recently introduced 

 shrub from Japan, is anoble-looking plant, 

 and promises to bear our climate. T. Icete- 

 virens has foliage resembling that of a,Sela- 

 ginella. T. pygmasa and T. prostrata are re- 

 markable for their peculiar dwarf depress- 

 ed habit of growth. [M. T. MJ 



THUNBERGIA. A considerable genus 

 of Acanthacece, containing a number of 

 climbing herbaceous plants from Africa 

 and Tropical Asia, with large coloured 

 flowers. The calyx is very short, truncate 

 or toothed, and concealed between two 

 large bractlets , the five corolla-lobes are 

 nearly equal and spreading ; the four sta- 

 mens have parallel-celled ciliate anthers; 

 the stigma is shortly bilobed ; the cap- 

 sule is globose and seed-bearing at the 

 base, and terminates in a flattened beak, 

 two-celled with one or generally two seeds 

 in each cell. The seeds are globular, hol- 

 lowed out on the inner face, and inserted 

 on a cupular expansion of the placenta. 

 The members of this genus are extensively 

 cultivated on account of the beauty of 

 their flowers. [W. C] 



THUNDER-DIRT. The name in New 

 Zealand for the gelatinous volva of Tleodic- 

 tyon, which is or was formerly eaten by the 

 natives. [M. J. B.] 



THUNDER-PLANT. Sempervivum tec- 

 torum. 



THUNDER-STROKE. See BROXTESIS. 



THUNIA. A genus of orchids, consist- 

 ing of one species from Tropical Asia for- 

 merly referred to Phajus. It is an herba- 

 ceous plant, with distant oblong strongly- 

 veined leaves, whose sheathing bases 

 clothe the stem ; the flowers are six or 

 eight together, in a pendulous raceme 

 furnished with large deciduous bracts; 

 sepals and petals nearly equal, white ; lip 

 shorter, the sides involute, the extremity 

 spreading fringed, white with lines of 

 purple hairs. [W. B. H J 



THURBERIA. A genus of Malvaceae, 

 comprising a tall handsome smooth her- 

 baceous plant, native of Texas. The leaves 

 are tripartite; and the flowers white or 

 red, with scattered black dots. The outer 

 calyx has three persistent leaves ; the 

 inner or true calyx is cup-shaped; the 

 stamens are united into a column, sur- 

 rounding or enclosing the undivided style; 

 the ovary is three-celled, each compart- 

 ment being partially subdivided into two, 

 and containing six to eight ovules ; the 

 stigma is club-shaped; the fruit capsular 

 three-celled three-valved, the valves with 

 hairy margins. [M. T. MJ 



THUS. Frankincense, a resinous exuda- 

 tiuu f mm Abies excelsa. 



THYLACIUM. A genus of the Cappa- 



ridaeecp, comprising certain shrubs, natives 

 of South-eastern Africa. The caJyx is in j 



