9. The Secretary and his assistants, during the session of Congress, will be required to illustrate new discoveries in science, and to exhibit new objects of art; distinguished individuals should also be invited to give lectures on subjects of general interest. * * * * * In accordance with the rules adopted in the programme of organization, each memoir in this volume has been favorably reported on by a Commission appointed for its examination. It is however impossible, in most cases, to verify the statements of an author; and, therefore, neither the Commission nor the Institution can be responsible for more than the general character of a memoir. * * * * * The following rules have been adopted for the distribution of the quarto volumes of the Smithsonian Contributions:-- 1. They are to be presented to all learned societies which publish Transactions, and give copies of these, in exchange, to the Institution. 2. Also, to all foreign libraries of the first class, provided they give in exchange their catalogues or other publications, or an equivalent from their duplicate volumes. 3. To all the colleges in actual operation in this country, provided they furnish, in return, meteorological observations, catalogues of their libraries and of their students, and all other publications issued by them relative to their organization and history. 4. To all States and Territories, provided there be given, in return, copies of all documents published under their authority. 5. To all incorporated public libraries in this county, not included in any of the foregoing classes, now containing more than 10,000 volumes; and to smaller libraries, where a whole State or large district would be otherwise unsupplied. OFFICERS OF THE SMITHSONIAN INSTITUTION. THE PRESIDENT OF THE UNITED STATES, _Ex-officio_ PRESIDING OFFICER OF THE INSTITUTION. THE VICE-PRESIDENT OF THE UNITED STATES, _Ex officio_ SECOND PRESIDING OFFICER. SALMON P. CHASE, CHANCELLOR OF THE INSTITUTION. JOSEPH HENRY, SECRETARY OF THE INSTITUTION. SPENCER F. BAIRD, ASSISTANT SECRETARY. W. W. SEATON, TREASURER. ALEXANDER D. BACHE, } RICHARD WALLACH, } EXECUTIVE COMMITTEE. RICHARD DELAFIELD, } REGENTS.