As with the post from last Monday noting a website that gave the various versions of the arms of the City of Paris over the years, here's a webpage that gives the history - through several different iterations, some of them pretty complex - of the changes to the coat of arms, not of a city this time, but of an entire nation.
The webpage "The Royal Arms of Canada - a Short History (http://www.heraldry.ca/misc/coatArmsCanada.htm) gives the history of the arms of Canada from its inception as a Dominion in 1867 through the arms as they exist at present.
And here is a rendition of the arms as they are used currently (the red and gold band circling the shield bears the motto of the Order of Canada, Desiderantes Meliorem Patriam, "They desire a better country"). Note how the mantling around the helm is in the form of red and white maple leaves. (If you're going to use a motif, like Canada does with maple leaves, then you really can't have too many. Or as someone once said, "Nothing succeeds like excess.")