where the slope differs by about 1 per cent from that in formula (2). The list contains 16 elliptical nebulae, 15 normal, and 6 barred spirals. The nebulae are fairly representative, except that few late-type spirals are included. This is an effect of selection due to the fact that nuclei become less and less conspicuous as the sequence progresses. The same result can be derived from a study of the differences, m_{n} – m_{T}, for the individual nebulae. The mean value is 1.55 ± 0.08, and the average residual is 0.60 mag. Means for the separate types are to be found in Table XIV. TABLE XIII Diameters and Nuclear Magnitudes =======+============+=========+================+=============== N.G.C. | Type | log d | m_{n} Hopmann | m_{n} Reduced -------+------------+---------+----------------+--------------- 221 | E2 | +0.42 | 9.84 | 11.85 1023 | SBa | .78 | 11.86 | 11.86 2841 | Sb | 0.78 | 12.08 | 11.19 3031 | Sb | 1.20 | 10.94 | 10.05 3115 | E7 | 0.60 | 10.83 | 11.09 3351 | SBb | .48 | 12.31 | 12.15 3368 | Sa | .85 | 11.68 | 11.43 3379 | E0 | .30 | 11.55 | 14.27 3412 | SBa | .40 | 11.59 | 11.59 3489 | Sb | .40 | 11.54 | 10.65 3626 | Sa | .28 | 12.37 | 12.12 3627 | Sb | .90 | 12.03 | 11.14 4125 | E4 | .30 | 11.74 | 13.04 4216 | Sb | .85 | 11.65 | 10.76 4278 | E1 | .0 | 12.02 | 14.38 4374 | E1 | .08 | 11.43 | 13.79 4382 | E4 | .48 | 11.77 | 13.07 4435 | E6 | .11 | 11.65 | 12.26 4438 | Sb | .54 | 11.83 | 10.94 4486 | E0 | .30 | 11.23 | 13.95 4546 | E6 | .18 | 11.75 | 12.36 4552 | E0 | .23 | 11.59 | 14.31 4569 | Sc | .65 | 12.05 | 10.57 4579 | SBc | .45 | 11.48 | 10.07 4621 | E5 | .30 | 11.60 | 12.56 4636 | E1 | .08 | 11.97 | 14.33 4649 | E2 | .30 | 11.57 | 13.58 4697 | E6 | .48 | 10.90 | 11.51 4699 | SBb | .57 | 10.72 | 10.56 4725 | SBb | .70 | 11.97 | 11.81 4736 | Sb | .70 | 10.36 | 9.47 5005 | Sc | .70 | 12.04 | 10.56 5033 | Sc | 0.78 | 12.38 | 10.90 5194 | Sc | 1.08 | 11.38 | 9.90 5322 | E3 | 0.15 | 12.10 | 13.76