Abstract
The histology and micro-architecture of different cells lining the olfactory epithelium in lesser spiny eel, Macrognathus aculeatus (Bloch), were analyzed with light and scanning electron microscopes. The leaf-like elongated olfactory rosette of the fish consists of 16 to 18 flat lamellae arranged on both sides of a narrow median raphe. Each lamella comprises a very restricted area of sensory epithelium on the extreme left corner, with the rest non-sensory epithelium. The sensory epithelium has two types of receptor cells-ciliated and microvillous, while the non-sensory epithelium comprises stratified epithelial cells, labyrinth cells, and mucous cells. The orientation of different cells on the olfactory epithelium has been correlated with the functional significance of the fish concerned.