Morphological, anatomical and histological studies on the olfactory organs and eyes of teleost fish: Anguilla anguilla in relation to its feeding habits

The morphology, anatomy and histology of the olfactory organ of Anguilla anguilla have been described. It was found that each olfactory chamber opens externally by an anterior inlet and posterior outlet nostrils. The olfactory rosette situated in each chamber is oval and the number of its olfactory lamellae in the olfactory rosette increases with the increase of body length. The olfactory epithelium of the lamellae is composed of receptor, supporting, basal and goblet cells. The average olfactory surface area is about 590.9% of the retinal area. Thus A. anguilla is a macrosmatic species ‘‘nose-fish’’ in which olfaction plays an important role in its feeding habit. It is noticed that, the photoreceptor cell layer in A. anguilla (bottom feeder) is made up only of rod cells.