a membrane enclosing and protecting the developing spores especially that covering the sori of a fern
例句
Sori borne near the costule, indusium spherical, membranous. 孢子囊群靠近中脉著生；囊群盖球形，膜质。
Indusium The flap of tissue, derived from the placenta, that encloses the developing sporangia in the sorus of a fern. 囊群盖：是一种起源于胎座（应为叶表皮译者注）的瓣片状组织，覆盖在蕨类植物孢子囊群中正在发育的孢子囊上。
Sori hemispheroid, in 2-3 series on each side along the costules, without indusium. 孢子囊群圆形，沿中脉两侧各排成2-3行，无囊群盖。
Sori 1-5 pairs borne on the lower surface of ultimate lobes at the end of basal veins; indusium dehiscent in two equal halves when mature. 孢子囊群1-5对，生于末回裂片下面近基部小脉顶端；囊群盖成熟时对开2裂。
indusium dehiscent in two equal halves when mature. 囊群盖成熟时对开2裂。
any fern of the genus Cystopteris characterized by a hooded indusium or bladderlike membrane covering the sori. 一种带有兜帽或像狸藻的膜一般的孢子囊的冷蕨属植物。
