In a large bowl, stir together the flour, sugar, whole wheat flour, cornmeal, and spices.
Using a pastry cutter, cut the butter into the flour mixture until it resembles coarse crumbs.
Remove ¾ cup of the crumb mixture for topping and set aside. This will serve as the streusel topping!
In a medium bowl, combine the eggs, pumpkin puree, molasses, buttermilk, and baking soda.
Add the pumpkin mixture to the crumb mixture and stir until just moistened.