Abstract
1. During a sixty day estivation period, the land pulmonate, Bulimulus dealbatus, metabolized 21.5 mg-tissue/g dry wt. Of the tissue consumed, protein and polysaccharide made up 57% and 35% of the loss. 2. By the third day after onset of estivation aerobic respiratory rates declined to 16% of the resting level. 3. Snails maintained in a 85% R.H. were active longer and accumulated urea faster than those snails in 14% R.H. The high concentrations of urea were probably related to an enhanced catabolism of protein and not to osmotic stress. 4. The water content of Bulimulus and the number of epiphragms formed was not correlated with the estivation humidity.