Excerpt from Proceedings of the California Academy of Sciences, Vol. 6 A greater surprise than the absence of the boreal birds mentioned was the presence of the Black-vented* and the Dark-bodied Shearwaters. Thousands of the former passed Monterey Bay on their way southward. Winter migration in birds nesting in the Northern Hemisphere is a well-known fact, there being continual movement south ward and northward as the zone of snow and ice advances and retreats, but migration southward in the Northern Hemisphere in winter to breeding grounds appears to have escaped the observation of ornithologists. Such a migra tion exists in the Black-vented Shearwater. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.