486 
ASTRONOMY: SHARES AND SHAPLEY 
ages for the background are in reasonably good agreement with those 
for the North Pole and the region of S Cygni given in the last column. 
There is no evidence of a variation of the condensation with color either 
before or after the deduction of the background stars. 
The distribution with respect to magnitude and distance, and magni- 
tude and color, is similar to that for N. G. C. 1647, although the color 
and magnitude relation is less clearly marked than was the case with 
that cluster. 
TABLE IV 
Color and Distance — Number of Stars in M 67 
COLOR 
ZONE 
TOTAI^ 
0-1 '.5 
l'.5-3'.5 
3 '.5-5 '.5 
5 '.5-7 '.5 
7'.5-9'.5 
9'.5-ll'.5 
a 
0 
2 
2 
0 
1 
1 
6 
/ 
5 
10 
9 
15 
11 
24 
74 
g 
8 
39 
34 
22 
12 
14 
129 
k 
2 
7 
9 
2 
1 
1 
22 
Totals 
15 
58 
54 
39 
25 
40 
231 
Relative area . . . 
2.25 
10 
18 
26 
34 
42 
132.25 
Density 
6.67 
5.80 
3.00 
1.50 
0.73 
0.95 
TABLE V 
Percentage of Colors in M 67 and Background 
COLOR 
CLUSTER ALONE 
TOTALS 
PERCENTAGES 
0'-3'.5 
3 '.5-7 '.5 
Cl. 
Bkgd. 
Cl. 
Bkgd. 
Other 
Regions 
a 
2 
1 
3 
3 
3 
3 
13 
/. 
9 
4 
13 
61 
11 
54 
47 
g 
k 
43 
42 
85 
44 
71 
40 
30 
9 
9 
18 
4 
15 
4 
9 
Totals 
63 
56 
119 
112 
100 
101 
99 
SUMMARY OF RESULTS 
1. Neither N. G. C. 1647 nor M 67 show any dependence of condensa- 
tion upon color which cannot be explained on the basis of included 
background stars. 
2. With the possible exception of an excess of a few bright stars in 
the center of N. G. C. 1647, there seems to be no dependence of con- 
densation upon magnitude. 
3. There is a marked relation between color and magnitude in N. G. C. 
1647; the connection is also evident, though less pronounced, in the 
case of M 67. 
