This flower was part of a bouquet, logic would suggest it was Queen Anne's Lace but all our investigations point instead to Hemlock. Unfortunately the flower head started to drop very quickly as the bouquet was several hours out of water but they had no coloured central flower and the head were more loosely bunched than the Queen Anne's Lace photos. I have added a photo that includes the leaves. I do have a better photo of the flowers but was only able to add 1 photo.