_Periodical Literature._--The reader must not suppose that the only literature relating to the subject that we are considering is to be found in the volumes that have been mentioned. The original descriptions and the life-histories of a large number of the species of the butterflies of North America have originally appeared in the pages of scientific periodicals and in the journals and proceedings of different learned societies. Among the more important publications which are rich in information in regard to our theme may be mentioned the publications relating to entomology issued by the United States National Museum, the United States Department of Agriculture, and by the various American commonwealths, chief among the latter being Riley's "Missouri Reports." Exceedingly valuable are many of the papers contained in the "Transactions of the American Entomological Society," "Psyche," the "Bulletin of the Brooklyn Entomological Society" (1872-85), "Papilio" (1881-84), "Entomologica Americana" (1885-90), the "Journal of the New York Entomological Society," the "Canadian Entomologist," and "Entomological News." All of these journals are mines of original information, and the student who proposes to master the subject thoroughly will do well to obtain, if possible, complete sets of these periodicals, as well as of a number of others which might be mentioned, and to subscribe for such of them as are still being published. There are a number of works upon general entomology, containing chapters upon the diurnal lepidoptera, which may be consulted with profit. Among the best of these are the following: "A Guide to the Study of Insects," by A.S. Packard, Jr., M.D. (Henry Holt & Co., New York, 1883, pp. 715, 8vo); "A Textbook of Entomology," by Alpheus S. Packard, M.D., etc. (The Macmillan Company, New York, 1898, pp. 729, 8vo); "A Manual for the Study of Insects," by John Henry Comstock (Comstock Publishing Company, Ithaca, New York, 1895, pp. 701, 8vo). HUGO'S "FLOWER TO BUTTERFLY" "Sweet, live with me, and let my love Be an enduring tether; Oh, wanton not from spot to spot, But let us dwell together. "You've come each morn to sip the sweets With which you found me dripping, Yet never knew it was not dew, But tears, that you were sipping. "You gambol over honey meads Where siren bees are humming; But mine the fate to watch and wait For my beloved's coming. "The sunshine that delights you now Shall fade to darkness gloomy; You should not fear if, biding here, You nestled closer to me. "So rest you, love, and be my love, That my enraptured blooming May fill your sight with tender light, Your wings with sweet perfuming. "Or, if you will not bide with me Upon this quiet heather, Oh, give me wing, thou beauteous thing, That we may soar together." EUGENE FIELD. THE BUTTERFLIES OF NORTH AMERICA NORTH OF MEXICO