Fig. 1. Anatomy and innervation of ciliated cells on the velum. (A) Lateral view of a velar lobe showing tubulin-like immunoreactivity in cell bodies and cilia along the pre- and post-oral bands. Scale bar, 20 µm. (B) Lateral view of the velum at a slightly deeper focal plane showing details of the pre-oral ciliated cells and a bundle of tubulin-like immunoreactive axons (arrows) at their bases. Scale bar, 20 µm. (C) At higher magnifications, serotonin-immunoreactive fibres and varicosities (arrows) can be seen near the bases of the pre-oral ciliated cells. Scale bar, 10 µm. (D) Lines of varicosities (arrows) exhibit Leu-enkephalin immunoreactivity. Pre-oral cells possess slender nuclei at their bases. Scale bar, 10 µm.