The temperature of one was 18.2°C. when the sun had nearly set and activity was tapering off, at an air temperature of 16.2°C. At 16°C. skinks in a terrarium with no access to sunshine for the most part showed no interest in food and kept out of sight under cover. When exposed their activity was directed almost entirely toward burrowing into the substrate or searching for objects beneath which to hide. One adult female was partly exposed by scraping away loose soil into which she had burrowed. A mealworm was then dropped just in front of her head. She tested it several times with her tongue and then ate it without emerging, her movements being much less brisk than they normally are in feeding. Probably this approximates the threshhold temperature for feeding behavior. At 19.5°C. the several skinks in this terrarium were moving about in the open although they were not exposed to sunshine, and they accepted food avidly when it was offered, but were much slower than at optimum temperatures. On May 16, 1951, when a pair of skinks were put together in a terrarium in the laboratory at 21°C., copulation ensued but it was of longer duration than in other observed instances, seemingly because of the relatively low temperature. Relatively few temperature readings on gravid or brooding females under natural conditions were obtained as they were easily disturbed and tended to desert their nests at slight provocation. To avoid desertions handling was kept to a minimum. Occasionally gravid females were caught in the open, but most of them were in nest burrows under flat rocks. These females found in nests were mostly cold to the touch, and the temperature readings taken on some of them usually approximated the air temperature, being either higher or lower (depending on whether the air was cooling or warming and whether the lizards were warmed by contact with rock or soil receiving sunshine). On May 23, 1952, 22 skinks were seen, four adult males, seven adult gravid females, and 11 young. Of these the adult females all were in nest burrows, and were cold and slow; consequently all of them were caught without difficulty. The males and young, however, were either fully warmed or warm enough to escape rapidly, so that only three of the young and no adult males were caught. Temperatures of the females tested were 25.6°, 23.6°, 23.5°, 22.3°, and 19.4°, and for the three young, 32.8°, 28.4°, and 28.4°. Air temperature varied from 20.5° to 24.8°. For the total of 30 females in nest burrows whose temperatures were taken in 1952, the average was 26.3°C, ranging from 16° to 34°. Gravid females, and those with nests and eggs were rarely seen in the open.