The distribution of the stars to tVie eleventh magnitude 41 



Gioupe 



A, 





D, 





I 



15 



19,5 



12,9 



6,0 



11 



25 



32,8 





15,G 



III 



40 



Gl, 8 



21 is 





Mean 



25 



33,8 



1K,0 





The amount of the decrease is accordingly for the whole set of plates more 

 than 60 per cent of the average density, and the decrease is greatly accelerated 

 when the density is augmented. 



It is evident, that if the Harvard Map is to be used for an investigation of the 

 distribution of the stars, the densities must be reduced in such a manner, that the 

 decrease of the density shall be eliminated. How this reduction is derived and 

 calculated will be shown below. 



Lnmls UMivei-sitet.s Arsskiift. N. F. AW. 2. Bd 10. 



