ASTRONOMY: ADAMS AND JAY 
241 
6. There appears to be some tendency for the stars to move along a line 
of galactic longitude about 260°, allowance being made for the motion of the 
centroid. This direction coincides nearly with that of the greatest star den- 
sity as determined by various observers. 
7. The stars of highest velocity, over 300 km., also appear to move along a 
line parallel to that of the major axis when the motion is referred to their com- 
mon center. This is shown in the figure by the positions of the apices. 
8. The average galactic latitude of the apices of the stars of high luminosity 
is nearly twice as great as that of the fainter stars, the values being 26° and 
14°. The latitudes of the apices of only four of the fainter stars exceed 26°. 
9. The average space-velocity of the stars of low luminosity is much larger 
than that of the brighter stars. Twenty-eight stars of average absolute mag- 
nitude 5.9 show a velocity of 216 km. Nine stars of absolute magnitude 0.4 
a velocity of 130 km. 
10. An extraordinarily large proportion of the stars in this list, 26 out of 37, 
are of types F and G. The successive types F, G, K and M show average 
space-velocities of 307, 156, 122 and 121 km. respectively, the weight of the 
determination for the last two types being rather low. Among the stars of 
t5^e F those of earlier spectral type show the larger velocities. Thus the 
six stars with spectra between Fo and F5 inclusive have an average velocity of 
365 km. as against 307 km. for all stars of the F type. 
The most important result of this brief investigation is the evidence for the 
marked influence of the condensation of matter in the plane of the stellar 
galaxy upon the motions of these relatively faint stars. Their susceptibility 
to stream motion is perhaps another result of the same general influence which 
is, no doubt, gravitational in character. Probably the most peculiar fact in 
connection with these stars is the spectral type of the stars of highest velocity. 
That a type which we are accustomed to consider as intermediate in the scale 
of stellar development should contain so large a proportion of the most rapidly 
moving stars is difficult of explanation unless we may assume that these stars 
are of exceptionally small mass. Since the relationship of velocity to absolute 
magnitude seems to be fairly well established this hypothesis may be worthy 
of consideration. 
