1. Davidia involucrata Baillon, Adansonia. 10: 115. 1871. 珙桐 gong tong Trees to 20 m high, with ascending bark. Petiole red, 3.6-7 cm; leaf blade adaxially bright green, broadly ovate, 8-15 × 7-12 cm, abaxially densely silky pubescent, strongly veined, adaxially finally glabrous, base cordate, margin dentate-serrate with acuminate teeth, apex acuminate. Flower heads terminal, ca. 2 cm in diam. on slender peduncles ca. 7 cm, on short lateral spurs; bracts 2(or 3), opposite, ovate to oblong-obovate, margin entire or serrate, larger one to 16 cm, smaller one ca. 1/2 as long. Fruit usually solitary, green with purple bloom, pear-shaped, 3-4 × 1.5-2 cm. Fl. Apr, fr. Oct. 2n = 40*, 42*.● Montane mixed forests; 1100-2600 m. Guizhou, W Hubei, W Hunan, Sichuan, N Yunnan.This species was listed as rare in China by Fang and Song (in Fu & Jin, China Pl. Red Data Book 1: 474-476. 1992).【引自:Flora of China】
落叶乔木,高15-20米,稀达25米;胸高直径约1米;树皮深灰色或深褐色,常裂成不规则的薄片而脱落。幼枝圆柱形,当年生枝紫绿色,无毛,多年生枝深褐色或深灰色;冬芽锥形,具4-5对卵形鳞片,常成覆瓦状排列。叶纸质,互生,无托叶,常密集于幼枝顶端,阔卵形或近圆形,常长9-15厘米,宽7-12厘米,顶端急尖或短急尖,具微弯曲的尖头,基部心脏形或深心脏形,边缘有三角形而尖端锐尖的粗锯齿,上面亮绿色,初被很稀疏的长柔毛,渐老时无毛,下面密被淡黄色或淡白色丝状粗毛,中脉和8-9对侧脉均在上面显著,在下面凸起;叶柄圆柱形,长4-5厘米,稀达7厘米,幼时被稀疏的短柔毛。两性花与雄花同株,由多数的雄花与1个雌花或两性花成近球形的头状花序,直径约2厘米,着生于幼枝的顶端,两性花位于花序的顶端,雄花环绕于其周围,基部具纸质、矩圆状卵形或矩圆状倒卵形花瓣状的苞片2-3枚,长7-15厘米,稀达20厘米,宽3-5厘米,稀达10厘米,初淡绿色,继变为乳白色,后变为棕黄色而脱落。雄花无花萼及花瓣,有雄蕊1-7,长6-8毫米,花丝纤细,无毛,花药椭圆形,紫色;雌花或两性花具下位子房,6-10室,与花托合生,子房的顶端具退化的花被及短小的雄蕊,花柱粗壮,分成6-10枝,柱头向外平展,每室有1枚胚珠,常下垂。果实为长卵圆形核果,长3-4厘米,直径15-20毫米,紫绿色具黄色斑点,外果皮很薄,中果皮肉质,内果皮骨质具沟纹,种子3-5枚;果梗粗壮,圆柱形。花期4月,果期10月。
【引自:中国植物志】