The present study of the lingual apparatus of the Ardea cinerea consists of two parts; anatomical descriptions of the lingual apparatus, and the functions and interactions of the different parts of the apparatus. Anatomical description covers mechanically functioning elements (i.e. bill, skeletal elements, muscles, epithelial structures of the tongue, and salivary glands). The study indicated that the relative increase in the bill length in proportion to the cranium is considered as an advantageous adaptation to the piscivorous mode of feeding. At the hind half of the anterior region of dorsal surface of the tongue a shallow median sulcus is distinguished macroscopically. Backwards to the sulcus a distinct median deep groove are observed. The dorsal surface of the anterior region of the tongue is relatively smooth without lingual papillae, whereas the posterior part is densely armed or occupied with lingual papillae-like teeth. Poor-developed lingual salivary glands are extending at the posterior part of the tongue. These glands are of abocrine type; their secretions are composed of proteins, in addition to neutral and acidic mucopolysaccharides and supposed that the polysaccharides contain a sulphate group.
Key words: Anatomy, tongue, hyoid apparatus, feeding adaptations, Ardea cinerea
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