perivitelline space Fluid-filled space between egg proper and egg capsule (chorion). The width varies between fish groups and so can be used in identification.

• 卵周隙在真正卵与卵鞘(绒毛膜)之间充满液体的空隙。宽度在鱼群之间会改变，如此能被用于鑑定上。