日本苞子草（黃背草）

Themeda triandra subsp. japonica (Willd.) Koyama, Grass. Jap. Neighb. Reg. 452. 1987. Culm slender, about 1.5 mm in diameter. Blade linear, less than 10 cm long by 3 mm wide, basal margins with glandular hairs; ligule chartaceous, 1-2 mm long, truncate, minutely ciliate on upper part and back. Spikelets paired, dimorphic, with 2 pairs of empty spikelets at base, forming a compound false panicle, interrupted by involucres; each empty spikelet covered with long glandular hairs on lower glume. The upper pedicellate, 1 /2 the width of the lower. Lower spikelet sessile, pubescent, about 5 mm long. Glumes coriaceous, as long as the spikelet: the lower linear-lanceolate, hirsute on back; the upper oblong, 2-keeled, margins inrolled and glabrous; lower lemma membranous, lanceolate, acute, about 3 mm long; upper lemma minute, membranous, about 2.5 mm long, apex prolonged into a long and hispid awn about 3.5 mm long. Caryopsis about 3 mm long, oblong; embryo linear, 1/2 the length of the caryopsis.

TAIWAN: Without locality or collectors name, Dec. 15, 1932.

Distributed in China, Korea and Japan.

This species is closely related to Themedu triandra Forssk, a widely distributed species which grows in the warm and tropical regions of the world.

midrib 中肋: (la)large:several vascular bundles

leaf surface 表面: (fla)flat surface

sclerenchyma 厚壁組織: (mistr)strand variable with size of vein

chlorenchyma 葉綠組織: (radia)cells radiate and lesser than
bundle sheath cell in width

bundle sheath 維管束鞘: (sk)single bundle sheath with
conspicuous chloroplast

buliform cells not well developed 泡狀細胞不發達: (smreg)epidermal cells gradually enlarge
from vein to intervein

chlorenchyma cell number between two adjacent veins: 3

chloroplast form in bundle sheath 束鞘細胞內之葉綠體型式: (out)large amount and in centrifugal site

mestome sheath 內束鞘細胞: (Xyms -)metaxylem pole adjacent with
outer bundle sheath

distance between two adjancent vein 脈間距: 59 micrometer

length/weidth ratio of bundle sheath in LS 束鞘細胞縱面長寬比: 3

chlorenchyma cell shape in LS 葉綠細胞縱面形狀: lobed