Bar synapses in the end buds of lamprey skin.

The end buds of lamprey epidermis have been considered to be similar to taste buds, but the synapses on the receptor cells are of the type with a dense mass surrounded by lucent vesicles, which is not found in gustatory cells. It is suggested that the end buds may belong to the lateralis sensory system and be involved in the light sensitivity of lamprey skin.