Preheat oven to 325 degrees.
Butter, flour and sugar an 8 1/2 x 4 1/2 inch loaf pan; set aside.
Whisk together the flour, baking powder and salt in a small bowl; set aside.
Using an electric mixer, cream the butter with 1 cup sugar in large bowl until mixture is light and fluffy.
Add the eggs one at a time, beating well after each addition.
Add the lemon peel.
Slowly mix in the reserved flour mixture alternately with the milk beginning and ending with the flour mixture.
Lightly coat blueberries with a small amount of flour (a scant tablespoon) by tossing in a separate bowl.
Gently fold blueberries into the batter.
Spoon batter into the prepared loaf pan.
Bake for about 1 hour 15 minutes or until golden brown and a wooden pick inserted into center, comes out clean.
Meanwhile, bring remaining 1/3 cup sugar and the lemon juice to boil in small saucepan, stirring until sugar dissolves. Keep hot for pouring.
Pierce top of hot loaf several times with a long wooden pick without touching the bottom of the loaf.
Slowly, pour the hot lemon mixture over the loaf in pan.
Cool for 30 minutes in pan on wire rack. Turn bread out of pan and cool completely on rack.
Makes 1 loaf or if using small pans, 4 to 5 loaves.