As in the preceding books the color-plates have been given much attention. Work and expense have not been spared to make the plates the best possible with the present knowledge of color-printing. Yet the illustrations are not exact reproductions. The colors are, at best, only approximations; for it is impossible by mechanical processes to reproduce Nature’s delicate tints and shades. The camera does not take colors as the human eye sees them; and the maker of the copper plate can not quite reproduce all that the camera has taken. The colors then depend on the judgment of the printer, who by selecting and mingling colored inks, reproduces as nearly as his materials permit, the shades in his eye and mind; but no two persons see exactly the same colors in any object; so his conception may differ much from that of the horticulturist or artist who saw the original plum, as do theirs from each other. Still it is hoped that the color-plates will be of great service in illustrating the text. All of the plums from which the plates were made came from the Station grounds; the illustrations, with a few exceptions which are noted, are of life size, as grown under the conditions existing at this place, and as far as possible all are from specimens of average size and color. Acknowledgments are due in particular to the plum-growers of New York who have furnished much information for _The Plums of New York_; to numerous institutions in all parts of the United States who have loaned botanical specimens; to Professor Charles Sprague Sargent for advice, information and the use of the Arnold Arboretum library and herbarium; to W. F. Wight of the United States Department of Agriculture, who has given most valuable assistance in describing the species of plums and in giving their range; to the Station Editor, F. H. Hall, who has had charge of the proof-reading; to Zeese-Wilkinson and Company, New York City, for their care and skill in making the color-plates; and to the J. B. Lyon Company, Albany, New York, for their careful work in the mechanical construction of the book. U. P. HEDRICK, _Horticulturist, New York Agricultural Experiment Station._ TABLE OF CONTENTS PAGE PREFACE v INDEX TO ILLUSTRATIONS ix CHAPTER I.—EDIBLE PLUMS 1 CHAPTER II.—PLUM CULTURE 100 CHAPTER III.—LEADING VARIETIES OF PLUMS 136 CHAPTER IV.—MINOR VARIETIES OF PLUMS 391 BIBLIOGRAPHY, REFERENCES AND ABBREVIATIONS 573 INDEX 581 INDEX TO ILLUSTRATIONS PORTRAIT OF WILLIAM ROBERT PRINCE _Frontispiece_ FACING PAGE