CONIFER. SILVA OF NORTH AMERICA. 123 
THUYA. 
_ FLowers naked, monecious, terminal, solitary ; stamens decussately opposite; 
anther-cells 2 to 4; scales of the pistillate flower 8 to 12, oblong, acute; ovules 2 or 3. 
Fruit an erect strobile maturing in one season. Leaves dimorphic, persistent. 
Thuya, Linneus, Gen. 378 (1737). — A. L. de Jussieu, Gen. i. pt. i. 97. — Baillon, Hist. Pl. xii. 34 (in part). — Mas- 
413. — Endlicher, Gen. 258. — Meisner, Gen. 352. — Ben- ters, Jour. Linn. Soc. xxx. 19. 
tham & Hooker, Gen. iii. 426 (excl. secs. Thuyopsis and Biota, D. Don, Lambert Pinus, ed. 2, ii. 129 (1828). — 
Chamecyparis). — Eichler, Engler & Prantl Pflanzenfam. Endlicher, Gen. Suppl. iv. pt. ii. 3: 
Platycladus, Spach, Hist. Vég. xi. 333 (in part) (1842). 
Resinous aromatic trees, with thin scaly bark, soft light yellow or red-brown durable straight- 
grained slightly fragrant wood, slender spreading or erect branches, pyramidal heads, flattened lateral 
pendulous or erect branchlets disposed in one horizontal plane forming an open distichous spray 
usually pale and stomatiferous below and often ultimately deciduous, naked buds and fibrous roots. 
Leaves opposite, imbricated in four ranks, scale-like, ovate, acute, glandular or eglandular on the back, 
persistent ; on leading shoots nearly equally decussate, appressed or spreading, remote by the lengthening 
of the nodes, rounded or slightly keeled on the back, acuminate with long slender points; on lateral 
branchlets, those of the lateral ranks much compressed, conspicuously carinate, and nearly covering 
those of the other ranks; on seedling plants linear-lanceolate, acuminate, spreading or reflexed, pale 
and stomatiferous on the lower surface. Flowers minute, moneecious, appearing in very early spring 
from buds formed the previous winter, the staminate and pistillate usually on different branchlets, 
terminal, solitary. Staminate flower ovoid, composed of a subsessile axis, with four or six decussately 
opposite stamens ; filaments short, enlarged into suborbicular eccentrically peltate connectives bearing 
on their inner face from two to four subglobose two-valved pendulous anther-cells opening below 
longitudinally ; pollen-grains simple. Pistillate flower ovoid or oblong, composed of from eight to 
twelve erect oblong acute slightly imbricated decussate scales, the central, or the lower (Biota) fertile, 
slightly thickened at the base on the inner surface by the ovuliferous scales bearing from two to four 
erect collateral orthotropous bottle-shaped ovules. Fruit ripening the first season, pale cinnamon 
brown, ovoid-oblong, erect; scales thin, leathery, oblong, acute, marked near the apex by the thickened 
more or less free mucronulate border of the enlarged flower-scales, those of the two or three middle 
ranks larger than the others, and fertile, with two or rarely three seeds, or, under the lowest, with 
one (Euthuya); or oblong, somewhat fleshy when fully grown, becoming woody at maturity, with 
thicker conspicuously umbonate scales, the lowest four usually fertile, and bearing each from two 
to four seeds (Biota). Seeds erect on the base of the scale, ovate, acute, compressed, light chestnut- 
brown ; testa membranaceous, produced into broad lateral wings, distinct at the apex, often slightly 
unequal and lighter colored than the body of the seed; hilum minute (Euthuya) ; or thickened, rounded 
or obscurely angled on the back, wingless, dark red-purple, marked on the oblique base by large 
oblong pale hilums; seed-coat thick, of two layers, the outer thick and crustaceous, marked externally 
with rufous fibres, the inner membranaceous (Biota). Embryo axile," in copious fleshy albumen ; 
cotyledons two, longer than the superior radicle.” 
1 Mirbel & Spach, Ann. Sci. Nat. sér. 2, xx. 261, t. 10. Gen. iii. 427). Fruit erect, its scales thin, leathery, oblong, acute, 
2 By Eichler (Engler & Prantl, Pflanzenfam. ii. pt. i. 97) Thuya mucronulate, those of the two or three middle ranks larger than 
has been divided into the following sections : — the others and fertile ; seeds compressed, light chestnut-brown, 
Evruuya. (Euthuya and Macrothuya, Bentham & Hooker, 
