Probably the chief interest of Table X lies in the result that the maximum intensity drop from background to line recorded for any of these stars is 2.50 magnitudes, corresponding to a light loss of ninety per cent. Except for the supergiant cF8 star and the Ca+ absorption for α Cassiopeiae and Hε for δ Cassiopeiae, the light remaining at the center of the line is at least fifteen per cent of the background intensity. On the average for all these strong absorption lines there is something like twenty-five per cent of the background light remaining at the center of the lines. The significance of these residual intensities will be discussed in a later publication, when the forms of the lines as shown by the data of Table IX will also be considered. TABLE XI RESIDUAL INTENSITIES AT LINE CENTERS, EXPRESSED AS PERCENTAGES OF BACKGROUND INTENSITY ┌───────┬───────┬───────┬───────┬───────┬───────┬───────┬──────┬──────┐ │ Star │ Class │ Hβ │ Hγ │ Hδ │ Hε │ K │ 4227 │ 4215 │ ├───────┼───────┼───────┼───────┼───────┼───────┼───────┼──────┼──────┤ │ε Ori │ B0│ 81│ 69│ 71│ 74│ │ │ │ │β Ori │ cB8│ 82│ 66│ 67│ 65│ 86│ │ │ │α Lyr │ A0│ 42│ 27│ 23│ 21│ 81│ │ │ │α CMa │ A0│ 41│ 28│ 26│ 26│ │ │ │ │α Cyg │ cA2│ 74│ 56│ 56│ 52│ 61│ │ │ │α Aql │ A5│ 51│ 47│ 51│ 25│ 48│ │ │ │δ Cas │ A5│ 25│ 26│ 24│ 14│ 26│ │ │ │δ CMa │ cF8│ 57│ 36│ 45│ <13│ <13│ 52│ 63│ │α Aur │ G0│ 67│ 50│ 59│ 22│ 21│ 59│ 72│ │α Boo │ K0│ │ 61│ 51│ │ │ 29│ 52│ │α Cas │ K0│ 79│ 68│ 60│ 10│ 10│ 47│ 52│ └───────┴───────┴───────┴───────┴───────┴───────┴───────┴──────┴──────┘ For the wider lines, especially those that are strong and heavily winged, the intensities derived in this paper are probably of the right order. Probably, however, the dispersion used is too small to reproduce satisfactorily the detail at the centers of lines as narrow as those of such stars as α Cygni and β Orionis. The difficulty introduced does not involve inaccuracy of plates, microphotometer, or process of measurement; it is concerned solely with the fact that the spectral region examined is so narrow that, with the dispersion used, the grain of the plate is not fine enough to reproduce the spectral detail. The same difficulty would prevent any recognition of the double reversal of the solar H and K lines, if they were studied with the present dispersion.