Many cadherin subtypes are expressed in the nervous system, but the expression of a single cadherin subtype is confined to a restricted group of neurons. In the chicken embryonic retina, cadherin-6B proteins are detected only at narrow zones in the synapse-forming layers, suggesting that this cadherin is used by only limited synapses. Double-stained for cadherin 6B (green) and nuclei (blue). Photographed by K. Tanabe.