H h This third volume of RC3 indudes data for galaxies between 12 and 24 . For convenience, we repeat the explanation of the catalogue entries below. Details of the reduction procedures, and Notes, References, and Appendices are in Volume 1. 2. The Catalogue The data for each galaxy are found on four successive lines on a single page. The entries are as follows: Column 1: Positions Line 1: RA and DEC = right ascension and dedination for the equinox 2000.0, precessed from the 1950.0 position in Column 1, Line 4, given to 0.1 second of time and 1 arcsec when available, and to 0.1 minute of time and 1 arcmin otherwise (Section 3.1.a). Line 2: land b = galactic longitude and latitude in the lAU 1958 system (Blaauw et al. 1960); both to O~O1. Line 3: SGL and SGB = supergalactic longitude and latitude in the RC2 system (Section 3.1.b), both to O~O1. Line 4: RA and DEC = right ascension and dedination for the equinox 1950.0 (Sec tion 3.1.a). Column 2: Names = commonly used designations for the galaxies (Section 3.2). Line 1: Names (e.g., LMC, SMC) or NGC and IC designations. Line 2: UGC (Nilson 1973), ESO (Lauberts 1982), MCG (Vorontsov-Velyaminov et al. 1962-1974), UGCA (Nilson 1974), and CGCG (Zwicky et al. 1961-1968) des ignations, given in that order of preference. MCG designations not listed here are given in UGC and ESO.

H h This third volume of RC3 indudes data for galaxies between 12 and 24 . For convenience, we repeat the explanation of the catalogue entries below. Details of the reduction procedures, and Notes, References, and Appendices are in Volume 1. 2. The Catalogue The data for each galaxy are found on four successive lines on a single page. The entries are as follows: Column 1: Positions Line 1: RA and DEC = right ascension and dedination for the equinox 2000.0, precessed from the 1950.0 position in Column 1, Line 4, given to 0.1 second of time and 1 arcsec when available, and to 0.1 minute of time and 1 arcmin otherwise (Section 3.1.a). Line 2: land b = galactic longitude and latitude in the lAU 1958 system (Blaauw et al. 1960); both to O~O1. Line 3: SGL and SGB = supergalactic longitude and latitude in the RC2 system (Section 3.1.b), both to O~O1. Line 4: RA and DEC = right ascension and dedination for the equinox 1950.0 (Sec tion 3.1.a). Column 2: Names = commonly used designations for the galaxies (Section 3.2). Line 1: Names (e.g., LMC, SMC) or NGC and IC designations. Line 2: UGC (Nilson 1973), ESO (Lauberts 1982), MCG (Vorontsov-Velyaminov et al. 1962-1974), UGCA (Nilson 1974), and CGCG (Zwicky et al. 1961-1968) des ignations, given in that order of preference. MCG designations not listed here are given in UGC and ESO.

This Reference Catalogue of Bright Galaxies is a result of the explosive growth of extragalactic astronomy over the last 15 years. With data on more than 23,000 galaxies, it includes all galaxies with apparent diameters larger than one arc minute, magnitudes brighter than about magnitude 15.5, and redshifts not larger than 15,000 km/sec, as well as many other objects of interest. Volume 1 contains the explanations and references; volumes 2 and 3 contain the catalogue proper. The catalogue gives for each galaxy the position, names, type and luminosity class, optical diameters, optical and infrared magnitudes, various color indices, and radial velocities.

A thought provoking study of the powerful impact of images in guiding astronomers' understanding of galaxies through time.