What does "velum" mean?

Velum: (Bot.) (a) See Veil, n., 3 (b). (b) A thin membrane surrounding the sporocarps of quillworts Isoetes).

Additional senses

  1. 2.(Zoöl.) A veil-like organ or part. Especially: (a) The circular membrane that partially incloses the space beneath the umbrella of hydroid medusæ. (b) A delicate funnel-like membrane around the flagellum of certain Infusoria. See Illust. a of Protozoa.

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