TIIALIA— TIGRIDA. 
heton"ic\im, has loose spikes of fragrant 
crimson flowers. Ex. 
THA'LIA. 1—1. (Orchidea.) [In honor of 
John Thalivis.] 
dcalha'ta, (p. Au. 2^.) spntha 2-flowered ; 
leaves ovate, revolute at the summit ; pani- 
cle white-pulverulent. S. 
THALICTRUM. 12—12. (Ranuncvlacea.) 
[From thallo. to flourish.] 
dio'icum, (meadow rue, w-r. M. 2^.) flow- 
ers diceciouf ; filaments iiliform ; leaves 
about 3-ternate ; leafets roundish, cordate, 
obtusely lobed, glalirous; peduncles axilla-, 
ry, shorter than the leaves. 1-2 f. | 
'puhes"cen!i, (w. Au. 21-) leafets woolly,! 
lobed, margin revolute, finely pubescent 
beneath. ! 
corrm'ti, (g-y. Ju. 2^.) leaves decompound; 
.eafets ovate, obtusely 3-lobed, glaucous be- , 
neath, with the nerves scarcely prominent ; 
flowers mostly dioecious; filaments sub- 
clavate ; fruit sessile, striate. 2-5 f. Wet 
grounds. 
clava'tum, (2^.) leaves glabrous, without 
stipes; flowers monoacious; filaments cla- 
vate ; pericarp compressed, with a very 
short style. S. 
alpi'num, a dwarf species. 
THAS"PIU!VI. 5—2. (.Umbelhferece.) [From 
the isle of Thaspia.J 
acteeifo'lhim, (Ju. 2X) leaves gash-biter- 
nate ; segments oval, equally dentate; um- 
bels sub- verticillate; lateral ones sterile. 3 
f. Canada. 
atropurpu'reum, (p. J. 2^.) radical leaves 
petioled, cordate, undivided ; caviline ones 
gash-pinnate ; segments 3 to 7, short petio- 
led, ovate, oblong, all cartilaginous-dentate. 
2-3 f. 
THE'A. 12—1. (MeKce.) [A Chinese name.] 
bohe'a, (bohea tea, M. .) flowers 6-petal- j 
led ; leaves oblong-oval, rugose. Trora : 
China and Japan. 
"nr^'idit, (green tea, Tp .) flowers 9-petal- ! 
J.1 ; leaves very long oval. Ex. I 
THER"iV[IA. 10—1. (LeL;uminos(r.) [From' 
thermos, temperature ; a "plant of warm cli- 
mates.] 
rhombifo'lia. (y. 2.^.) leaves ovate-rhom- 
boid, silky-pubescent beneath ; stipuh^s 
leaf-like, round, ovate, oblique, shorter than 
the petiole ; flowers racemed. S. 
THE'SIUM. 5—1. (JElea^ni.) [From a Greek 
word signifying garland.] 
nmbeUa'tiim, (false toad-flax, w. g. J. 
erect; leaves oblong ; umbels axillary, 3-5- 
flowered ; peduncles longer than the leaves. 
9-15 i. 
THLAS"PI. l4— 1. (Cruciferm.) [From thlao, 
to break, so called because it appears bro- 
ken.] 
bnrm-pasto'riR, (shepherd's-purse, w. M. 
0 ) hirsute ; silicles deltoid, obcordate ; rad- 
ical leaves pinnatifid. 
arveri"se, (penny-rres.s, w. J..@.) leaves 
oblong, sagittate, coarsely toothed, smooth ; 
pouch sub-orbicular, shorter than the pedi- 
-•el ; its wings dilated longitudinally ; flow- 
ers in a raceme. 1 f 
tubero'avm, (A p. %.) flowers large, rosa- 
-«oa» ; stem i-5 inches high, simple, pubes- 
cent ; upper leaves sessile , radical leaves 
long-petioled ; root tuberous, pouch orbic- 
ular. 
allia'ceum, {%.) leaves oblong, obtuse 
dentate, glabrous ; silicle sub-ovate, veutri« 
cose. Introduced. 
THU'JA. 19—15. (ConifercB.) [From thuon^ 
odor, so called from its fragrant smell.] 
occidenta'lis, (American arbor-vitae, M. 
.) branches ancipetal ; leaves imbricated, 
in 4 rows, ovate-rhomboidal ; strobiles ob- 
ovate. Mountains. A small tree with 
very tough branches. Leaves resembling 
scales. 
gigan"tea, leaves imbricate 4-ways, ovate, 
obtu.sish, closely incumbent, sub-equal ; 
strobiles loose ; scales oboval, 200 feet high, 
and 12 feet in diameter. 
articula'ta, produces the gum Sandaracb; 
the wood is said to resist fire, and is also 
supposed to be the sandal-wood of the an- 
cients. 
THY'MUS. 13—1, (LahiatcE.) \¥xom thuma, 
odor.] 
vidga'ris, (thyme, b p. J. 14..) erect ; leavea 
ovate and linear, revolute ; flowers in a 
whorled .spike. Ex. 
serpyV'lum, (wild thyme, b p. J. 11) stems 
branched, creeping ; leaves elliptic-ovate, 
obtuse, flat, petioled. ciliate at base ; flow- 
ers capitate. 4-8 i. Naturalized. 
lanngino'i^us, (lemon thyme, II- stena 
creeping, hirsute ; leaves obtuse, villose ; 
flowers capitate. Ex. 
grandijlo'ra, veiy ornamental. Ex. 
THY'SANOCAR'TUS. 14-1. [CrucifertB .) 
[From thasanos, fringe, and karpos, fruit, tho 
pods having fringe on the edge.] 
airvi'pest, flowers racemed, small ; leave» 
mostly radical, pinnatifid ; silicle pendulons 
stem solitary, erect. West of Ilockv Moun 
tains. 
oblongifo'lms, silicles nearly orbicular 
wingless, hispid, with uncinate hairs ; pe 
tals about half as long as the calyx ; leaves 
oblong, toothed, densely and stellatelj 
hirsute. Oregon. 
TIAREL"LA. 10—2. (Saxifrngoi.) [Fron. 
tiara, an ornarr)ent for the head.] 
cordifo'lia, (mitre- wort, w. M. 2^.) leavea 
cordate, acutely lobed, dentate; teeth ma- 
cronate ; scape racemed ; petals with long 
claws ; flowers in a simple terminal raceme 
Shady woods. 8-10 i. 
menzie'sii, (Z^.) leaves ovale, heart-shap 
ed, acute, lobes short, dentate; caulina 
ones alternate, distant; raceme filiform, 
somewhat spiked ; calyx tubular. 1 f. 
trijolia'ta, (ZJ].) leaves tern ate ; leafets 
sub-rhomboid, serrate, pilose ; racemes ter 
minal ; small corymbs of flowers alternate* 
calyx campanulate. 
TiGA'REA 11—1. (JLosoctOF.) 
tridenta'ta, (y. Ju. >).) leaves crowded 
towards the ends of the branches, 3 tooth- 
ed, villose above, hoary tomentose beneath ; 
flowers terminal, solitary. S. 
TI'GRIDIA. )5— 3. (Iridea.) [So called from 
its spotted appearance, resembling a tiger.] 
eiLs{for"mis, (tiger flower,) spatha 2-leav 
