#cambium  the inner layer of the periosteum
  supertype:  stratum  one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism)
  part of:  periosteum  a dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles; contains nerves and blood vessels that nourish the enclosed bone

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