February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index

A union list of serials commencing publication after Dec. 31, 1949.

Some vols. include supplemental journals of "such proceedings of the sessions, as, during the time they were depending, were ordered to be kept secret, and respecting which the injunction of secrecy was afterwards taken off by the order of the House".