70 Prof. Phillips on a Zone of Spots on the Sun. [Mar. 22. 



Fig. 11. The same spot after it had proceeded on the disk, so as to allow of all parts 

 being seen in their true proportions. March 1 3th, 2^ 30"^. The change of 

 figure in the whole penumbral space, and in the darkest parts, is so great that 

 it is difficult to be assured of the identity of any one point now visible with 

 the appearance shown on any occasion in February. Yet, in fact, on search- 

 ing carefully the neighbouring tracts of photosphere, we can discern what 

 appear to be traces of the spaces occupied by the old penumbra. This im- 

 portant observation was made, not by myself only, but also by friends who 

 were quite unaware of the interesting changes of form which had occurred. 



Fig. 12. March 14th, 11^ SO'". Here the spot is seen further modified ; gathered up 

 into a smaller and more regular shape, with a deep slit through the penumbra 

 into the umbra ; the detached penumbra on the left was lost after a further 

 day's motion. 



The Society then adjourned over the Easter Vacation to Thursday, 

 xipril 12. 



