Mallard 38. Mayhew 1952 May 23 Gray Lodge Refuge, Sutter Co., Calif. taken between 8:15 A.M. + 12 noon. at 8:15 A.M., in open shade, the air temp., 43 inches above the ground (waist high), was 24°C., the relative humidity was 35%. Nest 11 - The ♀ was gone when I reached the nest, but the eggs were warm. The nest is about 3 feet from water, the cover is about 30 inches high. There are 7 eggs in the nest. Temp. - 32°C., R.H. - 45%. Nest 23 - The ♀ was flushed from 9 eggs. The nest is about 20 feet from water, in cover about 30 inches high. Temp. - 31°C., R.H. - 45%. Ground temp. (9 A.M.) - 22°C., R.H. - 65%. Nest 22 - The ♀ was gone when I arrived, + the eggs were cold. This nest is well hidden under a brush pile. The nest contains 8 eggs. Temp. - 19°C., R.H. - 42%. Nest 24 - A ♀ Mallard was flushed from 13 eggs in this nest. The cover is about 18 inches high, the nearest water is about 150 yards away. There is lots of down in the nest, but the eggs are resting directly on the ground. Temp. - 34°C., R.H. - 35%. Water about 100 yards away. Nest 27 - A ♀ was flushed from a nest containing 1 egg. No down was present. 3 Ht. The cover, of pigweed + thistle, was about 24 inches high. Temp. - 28°C., R.H. - 45%. Nest 25 - The ♀ flushed at my approach to the nest, which contained 10 eggs.