1. Pigeons trained by releases along a constant compass line were repeatedly tracked to their lofts from the same training points 30-50 miles away. Their tracks differed from day to day by several miles, and the birds usually did not follow any obvious landmarks.
2. The pigeons were released from new release points and on many of the tracks followed a definite sequence of orientation methods: the birds began flying in the same compass direction that had got them home from the training point, then they apparently switched to a rather accurate navigation method which got them to within 10 miles of the loft, where they seemed to pilot by a few familiar landmarks to the loft entrance.
3. There is no evidence that most of the pigeons learned or could use landmarks extensively more than 10 miles from the loft, even over area which they crossed more than twenty times.
4. The flight of pigeons from the training points and new release points at distances of 13 miles or more depended strictly on the visibility of the sun.