<Tr> <Th> TH </Th> <Td> H2. 00.06. 1.00002 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of microanatomy (edit on Wikidata) </Td> </Tr> <P> Neurilemma (also known as neurolemma, sheath of Schwann, or Schwann's sheath) is the outermost nucleated cytoplasmic layer of Schwann cells (also called neurilemmocytes) that surrounds the axon of the neuron . It forms the outermost layer of the nerve fiber in the peripheral nervous system . </P> <P> The neurilemma is underlain by the myelin sheath (referred to as the medullary sheath in the included illustrations). In the central nervous system, axons are myelinated by oligodendrocytes, thus lack neurilemma . The myelin sheaths of Oligodendrocytes do not have neurilemma because excess cytoplasm is directed centrally toward the oligodendrocyte cell body . </P>

The neurilemma of axons in the pns is formed by