荚果的外壳或豆荚壳部分。
The pod shell of a legume fruit.

贝甲类、枝角类、介形类、蔓足类以及叶虾类甲壳动物的头胸甲特别延长扩大，向身体腹侧弯曲，形成的一块由左右瓣合成的蚌壳形甲壳。
The carapace of mollusks, branchiopods, bivalves, amphipods, and leaf shrimp is particularly elongated and enlarged, bending towards the ventral side of the body, forming a clamshell-shaped carapace composed of left and right valves.

内部的壳。
The inner shell.

卵外部的坚硬壳层。
The hard shell surrounding an egg.