SBb ----------+-------------+------------+--------------- 4699 | >19.5 | 10.0 | > 9.5 ----------+-------------+------------+--------------- Sc ----------+-------------+------------+--------------- 253 | 18.3 | 9.3 | 9.0 598 | 15.6 | 7.0 | 8.6 2403 | 17.3 | 8.7 | 8.6 2683 | >20.0 | 9.9 | >10.1 2903 | 19.0 | 9.1 | 9.9 4254 | 18.5 | 10.4 | 8.1 4321 | 18.8 | 10.5 | 8.3 4414 | >19.5 | 10.1 | > 9.4 4490 | 18.8 | 10.2 | 8.6 5194 | 17.3 | 7.4 | 9.9 5236 | 18.6 | 10.4 | 8.2 5457 | 17.0 | 9.9 | 7.1 ----------+-------------+------------+--------------- Irr. ----------+-------------+------------+--------------- LMC | 9.5 | 0.5 | 9.0 SMC | 12.0 | 1.5 | 10.5 3034 | >19.5 | 9.0 | >10.5 4449 | 17.8 | 9.5 | 8.3 6822 | 15.8 | 8.5 | 7.3 ----------+-------------+------------+--------------- The data are listed in Table XVI and are shown graphically in Figure 10. The luminosities of the brightest stars are given in photographic magnitudes. For the Magellanic Clouds, M 33, and N.G.C. 6822, these were obtained from published star counts. For M 31, 51, 63, 81, 94, and N.G.C. 2403, they depend upon unpublished counts, for which the magnitudes were determined by comparisons with Selected Areas. For the remaining nebulae, the magnitudes of stars were estimated with varying degrees of precision, but are probably less than 0.5 mag. in error. [Illustration: Fig. 10.—Relation between total magnitudes of extra-galactic nebulae and magnitudes of the brightest stars involved. Differences between total visual magnitudes of nebulae and the photographic magnitudes of the brightest stars are plotted against the total magnitudes. The dots represent cases in which the stars could actually be detected; the incomplete crosses represent cases in which stars could not be detected, and hence give lower limits for the magnitude differences. The diagonal line indicates the approximate limits of observation, fixed by the circumstance that, in general, stars fainter than 19.5 probably would not be detected on the nebulous background.]