Another one of the 700 Eucalyptus species. Yes, there are that many!!
This is the Eucalyptus macrocarpa (makros = large, karpos = fruit), which is native to the south-west of Western Australia.
Four of the operculums are still in place, with only one flower – with all its wonderful stamens popping forth :)
King’s Park Botanical Gardens, Perth – August, 2011
Note: this is a cropped version of the original posted image – as per sleuthi’s suggestion below