<Tr> <Td_colspan="2"> Illustration of the four different types of glial cells found in the central nervous system: ependymal cells (light pink), astrocytes (green), microglial cells (dark red), and oligodendrocytes (light blue). </Td> </Tr> <Tr> <Th_colspan="2"> Details </Th> </Tr> <Tr> <Th> Precursor </Th> <Td> Neuroectoderm for macroglia, and hematopoietic stem cells for microglia </Td> </Tr> <Tr> <Th> System </Th> <Td> Nervous system </Td> </Tr>

Which of the following are not types of neuroglia