CUTANEOUS AND PULMONARY GAS EXCHANGE IN THE SPOTTED SALAMANDER, AMBYSTOMA MACULATUM

Abstract

1. In Ambystoma maculatum, the lungs and buccopharyngeal mucosa become increasingly important in respiration at higher temperature. 2. The skin accounts for more than 50% of the total oxygen uptake at 15° C. and below. 3. Approximately 80% of the carbon dioxide produced is released through the skin at all temperatures except 5° C., where no measureable amount of carbon dioxide is released through the lungs and buccopharyngeal mucosa. 4. Lung and buccopharyngeal tidal volumes increased directly with temperature; and the rate of buccopharyngeal oscillations increased greatly at higher temperatures, while the rate of lung inspirations remained relatively constant. 5. Buccopharyngeal oscillations are of appreciable importance in the respiration of A. maculatum, especially at higher temperatures.