ULTRASTRUCTURE OF THE OLFACTORY ORGAN OF THE NEWT, CYNOPS-PYRRHOGASTER

The ultrastructure of the nasal sacs of the Japanese newt, Cynops pyrr hogaster, was studied by scanning and transmission electron microscopy . The paired nasal sacs of the newt are dorsoventrally flattened with a lateral nasal sinus off the main cavity of each sac. Throughout each sac is a series of ridges and grooves. In the main cavity, sensory ep ithelium with ciliated and microvillous receptor cells lines the groov es, and a thin, ciliated non-sensory epithelium lines the ridges. Secr etory glands are present in the lamina propria. In the lateral nasal s inus, the ridges are lined with a thick, non-ciliated sensory epitheli um that lacks glands. This region resembles and may function as a prim itive vomeronasal organ.