( m ) 



nebulae being about tlie same in the two galactic hemispheres) would 

 then reveal itself in those two segments, so that the soutliern galactic 

 segment J3 (lying on the northern hemispliere) is found to be richer 

 in nebulae than the northern galactic segment A (lying on the 

 southern hemisphere), and the difference would be most marked in 

 the small and faint nebulae. 



TABLE V. 



Nebulae in the segments between the celestial equator and the 



galactic equator. 

 A, segm. north, gal. hemisjihere B, segm. south, gal. hemisphere 

 (southern hemisphere) (northern hemisphere) 



bright nebulae . . . 152 71 



faint nebulae . . . 754 1043 



In table V the difference meant is indeed xqyj great for the faint 

 nebulae; it is remarkable, however, that for tlie bright ones thei'e 

 is a large difference in the opposite sense. This raises the surmise 

 that the possible influence mentioned above does not play a prepon- 

 derating part. 



If we compare the structui-e of segment /I with that of the remaining 



part of the northern gal. hemisphere it appears that tiie density of 



nebulae in the segment is only 0.6 — which is by no means surprisijig 



as it borders upon the galactic plane — but it is very remarkable 



faint . 



that the proportion — ni the segment, 4.96, is exactly the same 



bright 



in the remaining part of the northern gal. hemisphere, viz. — ; — - = 4.95. 



The relation in the segment B, the southern galactic segment, is 



on the other hand quite different: = 14.7. This points very 



^ bright ^ ^ 



markedly to a surplus of faint nebuhie in the southern galactic 



segment situated on the northern hemisphere, and this circumstance 



together with the presence of the Nubeculae and their relation with 



the accumulations of nebulae in the southern gal. hemisj)here makes 



it very probable that the structure of the soutliern galactic sky with 



regard to the nebulae differs entirely from that of the northern 



galactic sky. 



In the very improbable case that by a more accurate survey the 



northern galactic segment would be enriched so considerably by faint 



nebulae that the proportion of the immbers of bright and faint 



