In the amniotic egg of oviparous reptiles, most sources of energy required for embryonic development must be available within the egg, excluding oxygen and water, which are required from the environment. Variation in the metabolic patterns among different species of embryonic birds has been well described. These studies have recognized two patterns of oxygen consumption during development: a sigmoidal curve and a linear relationship between metabolism and incubation time. The sigmoidal curve is reported in most other species of reptiles, excluding snakes. Snakes are underrepresented in this type of research, although some studies have indicated an exponential curve for metabolic rate during development. Other members of Squamata do not exhibit this pattern, making this a potentially derived state. The aim of this study was to generate an oxygen consumption curve for the corn snake, Pantherophis guttatus, during development to test the hypothesis that embryos will exhibit an exponential increase in oxygen consumption over time. Oviposited eggs were placed in chambers for 24-hour periods and percent oxygen was recorded throughout development. Embryos were staged and the carcass and yolk were weighed separately. Results indicated a steady incline in oxygen consumption during the earlier stages of development, with a rapid increase as hatching approached. Our data support the hypothesis that the developmental pattern of oxygen consumption in snakes differs from other squamates.