Also, just to add, a comma before the 'and' in this case isn't needed because without the appositive the sentence would read, "It deserves many prizes and the affections of generations of readers." You don't use a comma before the 'and' of the last item in a list unless the list has three or more items. (In that case, it's personal preference of whether or not to use one.) Since "the affections of generations of readers" isn't a complete sentence, the comma-conjunction rule doesn't apply.
I hope that makes a little bit of sense. Sorry for going all nerdbabble on you.
Hope that helps!