Note 94 — Chapter VI · THE FEATHERED CONQUERORS OF THE AIR. Part I.—Their Wanderings over Sea and Marsh, Desert and Plain.
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Some chamæleons and geckos also have air-tubes passing from the lungs into the body, and the crocodile’s skull is full of air-cells; but the two phenomena are not connected as in birds, and other parts of the skeleton or of the skin-covering, being heavy, have a counteracting effect.