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ASTRONOMY: H. SHAPLEY 
bright stars of types B and A throughout this region may be assigned 
to the duster, but also the rich belt of stars of all types with magnitudes 
from three to seven. Across from Orion and Canis Major, on the other 
side of the Milky Way and at the same distance from the galactic equa- 
tor, we find in Cancer and Hydra no counterpart of this richness in 
-60° - 
Fig. 3. Distribution of faint B stars, from the Henry Draper Catalogue. The wide 
extent of the bright double cluster in Perseus is shown by the points near dedination + 60° 
and right ascension 2^. 
naked-eye stars; and the intervening constellation Monoceros is almost 
destitute of stars brighter than the sixth magnitude, although it lies along 
the central line of the Milky Way and is surpassingly bright in tele- 
scopic stars of the far-extending galactic segment. 
From the recent studies by Walkey, CharKer, and Stromberg it is 
known that the center of the stellar system that immediately surrounds 
