f 124 ) 



nebul.ae agrees more or less with that in segments B, i.e. 1:15, 

 we should coiiiit thei-e 2500 iiclmlae against 3200 in the remaining "/m 

 of the northern galactic hemispiiere, aiid the increase towards the 

 Pole, at least for the faint nebulae, would then almost disappear in 

 the northern galactic hemisphere. 



But whether the numhei' of faint nebulae remains 754 or increases 

 to 2500, in either case a symmetrical increase is out of the question 

 and hence there is no reason why we should adopt Cleveland Abbe's 

 prolate ellipsoid which moreover was not very pi-obable. 



Several consideraticms plead against the view that the nebulae 

 must be considered as distant galactic systems; the most important, 

 which has been expressed half a century ago, is the occurring together, 

 in most cases even in streams, of nebulae and stars, and also the 

 existence of stars and nebulae in the Nubeculae: (it is obvious that in 

 such cases we liavc to (hi witii objects of the same order of magnitude). 

 Moreover we have the well-established fact tiiat a star may pass into 

 a nebula. (Comp. Valentinek, Handwiu-terbuch d. Astron. Ill, 2, 

 p. 524; also MouLTON, Astrophys. Journal XI, 2, Sc^haeberle, Nature, 

 Vol 09, No 1785, Seeliger, Abh. bayer. Akad. XIX, p. 572). 

 Should on the other hand a "distant galactic system" be visible to 

 us it can only appear to us as a nebula. Hur the scarcity of nebulae 

 in the galactic region, if that phenomenon is real, points to an un- 

 mistakable organic connection between the great mass of the nebulae 

 and our system of stars. 



If then we may accept that the basis on which Cleveland Abbe 

 built his theory of the ellipsoidal figure does not hold and if moreover 

 we need not consider the nebulae as being situated at enoi'mously vast 

 distances on either side of liio Milky Way, luil it', on the contrary, 

 it is far more likely that these (Hstances are comparable with those 

 of the stars, it becomes probable tiiat the greater j)art of the nebulae 

 are contained in a space similar to the ol»late spheroid in which 

 Seeliger places our whole stellar system, in otiier words : we may 

 begin by adopting that the great mass of the nebulae belongs to 

 our stellar system and that they are asymmetrically scattered on 

 either side of the chief plane. 



Moreover, if we supposed that the great mass of the nebulae were 

 systems outside our own, the problem would not be capable of further 

 development. We must therefore not start fron) such an hypothesis. 



