片状的

Bracteoles and sepals 7-11(-17), imbricate; outer 2-5(or 6) bracteoles and sepals caducous after anthesis.

小苞片和萼片7-11(-17)，成鳞状；外部2-5(或6)小苞片和萼片早落的在花后。

Sepals (2-)4 or 5(or 6), imbricate or decussate or rarely wholly united in bud, inner ones sometimes petaloid.

萼片(2-)4-5(-6)，在芽期覆瓦状排列或交互对生或很少完全合生，内部的萼片有时花瓣状。

The reproductive development process of birch was described as follows: Male inflorescences extended from apical bud in early June. In later June, stamen primodium was differentiated in the bract of male inflorescence and the differentiation of bract was generated in female inflorescence. During July, anther layers and archesporial cell were differentiated in anther, then archesporial cell developed into mother microspore cell. Pistil primodium came into being at the same time. In early part of August the meiosis of mother microspore cell started. In later August, mono-nucleus microspore was formed. After September, both male inflorescence and female inflorescence were dormant.

白桦的生殖生长发育过程如下：6月初，雄花序从顶芽中生长出来。6月中下旬，雄花序苞片上分化出雄蕊原基，雌花序分化出苞片。7月，雄花花药分化出花药壁和孢原细胞，孢原细胞演化为小孢子母细胞，雌花序苞腋处分化出雌蕊原基；8月中上旬，小孢子母细胞减数分裂，8月下旬形成单核小孢子；9月后雄花序以单核小孢子状念越冬，雌花序以雌蕊原基状念越冬。

Stems simple or multibranched; leaf blade lanceolate or elliptic-lanceolate to ovate, 5-10 mm wide; racemes opposite to leaves or axillary; bracts ovate-lanceolate, caducous; inner sepals obovate-oblong.

茎单生或多分枝；叶片披针形的或椭圆形披针形到卵形，5-10毫米宽；总状花序与叶对生或腋生；苞片卵状披针形，早落；内部萼片倒卵状长圆形。

Rays (9–)11–25; bracts and bracteoles pinnate/pinnatifid at apex, rarely acuminate.

伞辐(9-)11-25；苞片和小苞片羽状/羽状半裂的在先端，很少渐尖。

Sessile spikelet subterete; callus long, pungent, bearded; lower glume leathery, obtuse; upper glume awnless; lower floret reduced to a hyaline lemma; upper lemma stipitiform, entire, passing into a stout geniculate awn with hairy column.

无梗小穗近圆柱状；胼胝体长，锐尖，具髯毛；更低的颖片革质，钝；上面颖片awnless；更低的小花退化至一透明的外稃；膝曲的柄状，全缘，度过的上面外稃成为一粗壮具有毛柱状。

Spikelets elliptic or elliptic-oblong, 2–10 mm, stramineous or purplish, florets 3–10; glumes ovate-lanceolate; lower glume 0.7–1.5 mm; upper glume 1.1–2 mm; lemmas ovate-lanceolate, 1.8–2.7 mm; palea keels scabrid.

小穗椭圆形或椭圆形长圆形，2-10毫米，麦秆色的或带紫色，小花3-10；颖片卵状披针形；更低的颖片0.7-1.5毫米；上面颖片1.1-2毫米；卵状披针形的外稃，1.8-2.7毫米；内稃龙骨粗糙。

Inflorescences terminal or axillary, subcapitate to capitate, with 2 to many spikelets; spikelets usually 1-flowered; bracts herbaceous; bractlets 2, membranous.

圆锥花序顶生或腋生，对头状，具2到多数小穗近头状；通常的小穗1花；苞片草质小苞片2，膜。

Scape suberect, usually shorter than leaves, loosely bearing 6-12cm or more flowers; bracts 5mm long; pedicel including ovary 4cm long; flower light yellow-green, faintly fragrant like Osmanthus fragrans ; dorsal sepal nearly oblong, 4.5-6cmlong, 1.2-1.8cm wide, yellow-green ,base tinged purple-brown on back, lateral sepals oblique-oblong, slightly narrow, petals narrower than sepals, 5-12mm wide, light yellow-green, spotted purple-red at base; lip slightly short-clawed, 3-lobed, side lobes erect, striped purple-red, mid-lobe somewhat reflexed, waved at margin, disk pubescent above, with 2paralles lamellae, long-hairy.

花葶近直立，常短于叶，疏生6~12朵或更多朵；花苞片长约5mm ；花梗连子房长约4cm ；花浅黄绿色，稍有桂花香气；中萼片近矩圆形，长4.5~6cm ，宽1.2~1.8cm ，黄绿色，背面基部有紫褐色晕，侧萼片斜矩圆形，稍窄；花瓣比萼片窄，宽5~12mm ，浅黄绿色，基部有紫红色的小斑点；唇瓣略有短爪，3裂，侧裂片直立，具紫红色条纹，中裂片略反折，边缘波状，唇盘上表面被短柔毛，2条褶片平行，生长毛；合蕊柱须长，3~4.2cm 。

Umbels compound, terminal on stem and branches; bracts absent; umbellules many-flowered, capitate; bracteoles several, lanceolate or ovate lanceolate, entire; pedicels obsolete.

复伞状花序，在茎和分枝上顶生；苞片无小伞形花序多花的，头状；小苞片数个，披针形或卵状披针形，全缘；花梗过时。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。