Figure 3. Microphotographs of the mesopallium of six avian species. Black arrowheads indicate neurons with perineuronal glia (white arrowheads) and the green arrowheads indicate unclustered neurons. The red arrowhead shows a neuron cluster.

The question mark indicates a neuron apparently surrounded by perineuronal glia (when tissue prevented unambiguous identification of glia). (A) NC crow; (B) Japanese jungle crow; (C) Australian magpie; (D) Indian mynah; (E) zebra finch; (F) pukeko. Scale bar: 100 µm.