Mayhew 1952 Mallard 40. May 23 Gray Lodge Refuge, Sutter Co., Calif. was about 24 inches high. Temp. - 33.5°C, R.H. - 40%. Nest 28 — At 11:15 A.M. a ♀ was flushed from a nest about 150 yards east of nest 17 along the edge of the road. There was lots of down present, with 5 eggs. The cover consisted of thistles about 24 inches high. Temp. - 35.5°C., R.H. - 31%. Nest 19 — ♀ was gone when I arrived. There was lots of down present, along with 7 eggs. Water was about 50 feet away. Cover consisted of foxtails about 26 inches high. Temp. - 36°C., R.H. - 31%. Nest 13 — ♀ flushed at my arrival. There was lots of down. The foxtail cover was about 18 inches high. Water was about 50 feet away. 9 eggs were in the nest. Temp. - 38°C., R.H. - 34%. Nest 21 — This nest is about 20 feet from nest 13, so both ♀ flushed at the same time. About 5 minutes elapsed before I could take a reading. No down was present. Cover was the same as for nest 13, 8 eggs were present. Temp. - 34°C, R.H. - 25%. At 11:45 A.M. readings were taken on the ground & at waist height (43 inches). These were: ground waist high. Temp. 36°C. 35°C. R.H. 25% 22%