Air-bladder synonyms

The oesophagus is provided often with caeca which in Syllids and Hesionidae have been found to contain air, and possibly therefore perform the function of the fish's air-bladder.

European mackerel are of two kinds, of which one, the common mackerel, Scomber scomber, lacks, while the other possesses, an air-bladder.

But, on the ground of their air-bladder being closed, or deprived of a pneumatic duct communicating with the digestive canal, such as is characteristic of the Malacopterygians, they were removed from them and placed with the flat-fishes, or Pleuronectidae, in a suborder Anacanthini, regarded as intermediate in position between the Acanthopterygians, or spiny-finned fishes, and the Malacopterygians.

The suborder Anacanthini is, nevertheless, maintained for the Muraenolepididae Gadids and two related families, Macruridae and Muraenolepididae, and may be thus defined: - Air-bladder without open duct.

These are a chain of small bones belonging to the first four vertebrae, which are much modified, and connecting the air-bladder with the auditory organs.