#tunica__tunic__adventitia  an enveloping or covering membrane or layer of body tissue
  supertype:  tissue_layer__membrane  a pliable sheet of tissue that covers or lines or connects organs or cells of animals
  subtype:  albuginea  whitish tunic
     subtype:  sclera__sclerotic_coat__scleroticcoat  whitish fibrous membrane (albuginea) that with the cornea forms the outer covering of the eyeball
     subtype:  tunica_albuginea_testes  whitish cover of the testicle

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