Data on the thermoregulation of Anolis limifrons in Panama suggest that at least some tropical species are less warm adapted than previously thought. Anolis limifrons has a lower minimum voluntary temperature, eccritic temperature, and critical thermal maximum than a majority of the temperate zone lizards thus far studied. Thermoregulatory adjustment is by behavioral mechanisms as indicated by observations on basking and orientation. A seasonality in the preferred temperature is indicated by field data from the wet and dry seasons. It is suggested that the lower preferred temperature in the dry season is an adaptation to conserve water or minimize water loss. Anoles (A. limifrons and A. frenatus) in colsed canopy forests are less warm adapted than the grassland A. auratus, whereas an ecotone species (A. tropidogaster) is intermediate in its thermoregulatory characteristics. Differences in dermal morphology in three species of Panamanian anoles are suggested to be an adaptation to varied capacities of heat gain.