Reports of commissions of the International Astronomical Union and related correspondence, including the following items:

Circular to Directors of National Ephemerides concerning 'Apparent Places of Stars', 1948.

Report of Commission 18 on 'Différences de Longitudes par Télégraphie sans fil', 1948.

Report of Commission 20 on the calculation of ephemerides and perturbations of minor planets, 1948.

Report of Commission 39 on international observatories, 1948.

Report of Commission 31 on the development of the Time Service at the Royal Greenwich Observatory, 1948.

Report of Commission 8 on meridian astronomy, 1947.

Report of Commission 20 on minor planets, comets and satellites, 1947.

Report of Commission 38 on the exchange of astronomers, 1947.

Copy of a minor planets ephemerides for 1947.

Report of the work at the Royal Observatory on polaris parallax plates, 1938.

Report of Commission 4 on the calculation of the apparent places of stars, 1938.

Report of Commission 36 on spectrophotometry, 1938.

Report of Commission 24 on parallaxes and proper motions, 1938.