A large number of other periodicals devoted to entomology have been issued, principally in Europe, but after continuing for a year or more their publication has been abandoned, and they are not included here. Important entomological papers have also been published in many serials devoted to zoölogy or the natural sciences generally. Among them may be mentioned the following:

LIST OF MORE USEFUL WORKS ON ECONOMIC ENTOMOLOGY.

ENTOMOLOGICAL WORKS PUBLISHED BY THE UNITED STATES ENTOMOLOGICAL COMMISSION AND BY THE UNITED STATES DEPARTMENT OF AGRICULTURE.

UNITED STATES ENTOMOLOGICAL COMMISSION.

(Members of the Commission: C. V. Riley, A. S. Packard, jr., and Cyrus Thomas.)

BULLETINS OF THE DIVISION OF ENTOMOLOGY, U. S. DEPARTMENT OF AGRICULTURE, UNDER DIRECTION OF C. V. RILEY, ENTOMOLOGIST.

SPECIAL REPORTS AND BULLETINS.

HOW TO OBTAIN ENTOMOLOGICAL BOOKS AND PAMPHLETS.

Comparatively few of the works treating of the classification of North American insects have been published as separate books; but such as have been so published, if of comparatively recent date, can be obtained through the regular book trade. By far the greater number of the monographs and synopses mentioned in the preceding pages have been published in scientific periodicals and in the proceedings or transactions of scientific societies. These may be obtained either through the societies or through the publishers; but single volumes of transactions or proceedings, and more especially single papers, are seldom sold, and the older volumes are liable to be out of print. Moreover, the expense attending the purchase of all of the periodicals containing the publications on a given order of insects will be so great as to put them beyond the reach of most entomologists. The custom of placing at the disposal of authors a number of separate copies of their papers overcomes this difficulty to some extent and creates a small supply. Thus it often happens that a person interested can obtain a copy of a scientific paper by addressing the author personally. Many of these separate copies also fall into the possession of dealers in second-hand books, and may be purchased from them. The American Entomological Society of Philadelphia, and also a few other societies here and in Europe, offer for sale from their duplicates many of these authors' extras, and in some cases publish lists. There are, moreover, certain business establishments which make a specialty of the sale of works and pamphlets on natural history, including entomology, and it is chiefly through such establishments that the student is enabled to secure the larger portion of the works needed.

By subscribing to the entomological periodicals published in this country (a matter of but slight expense) the student may keep abreast of the current literature. Short book reviews or notes published therein call attention to the more important publications in other countries. Moreover, the Zoölogischer Anzeiger, edited by Prof. J. Victor Carus, in Leipzig, Germany, and published every fortnight, gives a tolerably complete bibliography of the current entomological literature at intervals of about six or eight weeks. The “Naturæ Novitates,” published every fortnight by R. Friedlaender & Sohn, Carlstrasse, 11, Berlin, Germany, gives the titles of most recent works and pamphlets.

There are also three great annual publications, viz: “Die Fortschritte auf dem Gebiet der Entomologie,” published in Wiegmann's “Archiv für Naturgeschichte;” “The Zoölogical Record,” published by the Zoölogical Record Society, in London, England; and the “Zoölogische Jahresberichte,” published by the Zoölogical Station at Naples, Italy, which give the full literature of the previous year, discussing the more important papers and giving a list of the new species, besides other information. These three publications are almost indispensable to the student in any branch of zoölogy, and some one of them at least ought to be found in every public library in the country. The volumes of the “Zoölogische Jahresberichte” since 1887 contain no titles upon systematic and classificatory zoölogy, but only such as refer to biology.

A not inconsiderable portion of the North American literature on the classification of insects has been published by the Government of the United States through various channels, foremost among which are the Smithsonian Institution, the U. S. Department of Agriculture, the U. S. National Museum, the U. S. Geological and Geographical Survey, and the various surveys of the Territories. Some of these publications are distributed free of cost; while others, like certain of the publications of the Smithsonian Institution and the Geological Survey, are sold at a moderate price to cover the cost of publication. Many of them are out of print, and can only be obtained through natural history book-dealers.

Of the more general works, some may be obtained direct from the publishers, and in such cases the publishers are mentioned in the general list. The older works are mostly out of print and can only be obtained from second-hand dealers. The current State reports of Lintner and Forbes may be obtained from the secretaries of the respective State agricultural societies at Albany, N. Y., and Springfield, Ill., while the bulletins and reports of the entomologists of the various State experiment stations, of which a large number are being published, may be obtained from the directors of the respective stations. The older reports of the State entomologist of Missouri and the State entomologists of Illinois (Walsh, Le Baron, and Thomas) are all out of print and can only be obtained by purchase from second-hand dealers. The same may be said of the well-known and oft-quoted reports of Dr. Fitch, which were published with the old volumes of the Transactions of the New York State Agricultural Society.