#sheath.natural_covering__case  an enveloping structure or covering enclosing an animal or plant organ or part
  supertype:  natural_covering__naturalcovering__covering__cover  a natural object that covers or envelops; "the fox was flushed from its cover"
  subtype:  theca  outer sheath of the pupa of certain insects
  subtype:  lorica  a hard protective sheath as secreted by certain protoctists e.g.
  subtype:  medullary_sheath__medullarysheath__myelin_sheath  a layer of myelin encasing (and insulating) the axons of medullated nerve fibers
  subtype:  neurolemma__neurilemma  thin membranous sheath around a nerve fiber
  subtype:  husk  outer membranous covering of some fruits or seeds
     subtype:  cornhusk  the husk of an ear of corn
     subtype:  hull.husk  dry outer covering of a fruit or seed or nut
        subtype:  shell.hull  the hard usually fibrous outer layer of some fruits especially nuts
           subtype:  nutshell  the shell around the kernel of a nut
     subtype:  seedcase__pod__cod  the vessel that contains the seeds of a plant (not the seeds themselves)
        subtype:  pea_pod__peapod__peasecod  husk of a pea; edible in some garden peas
     subtype:  bract  a modified leaf or leaflike part just below and protecting an inflorescence
        subtype:  epicalyx__false_calyx__calycle__calyculu  a group of bracts simulating a calyx as in a carnation or hibiscus
        subtype:  bracteole  a small bract
        subtype:  spathe  a conspicuous bract surrounding or subtending a spadix or other inflorescence
        subtype:  involucre  a highly conspicuous bract or bract pair or ring of bracts at the base of an inflorescence
        subtype:  glume  small dry membranous bract found in inflorescences of Gramineae and Cyperaceae
           subtype:  flowering_glume__floweringglume__lemma  the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae

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