NOTE.—This periodical is issued by the Agriculture Department in cooperation with the Association of Land-Grant Colleges and Universities. As the edition is limited it is not sent free to individuals, but only to libraries of experiment stations, colleges, technical schools, and universities, and to laboratories, divisions, offices, and departments on whose staffs are several technically trained men in biological, chemical, or physical sciences. It is also sent to such institutions as make suitable exchanges of their publications for those of the Agriculture Department.