1 lemon, cut in 1/2
1 lb. med. shrimp, shelled and deveined
1/4 c. lemon juice
3/4 c. Roma tomatoes, diced
1 tsp. black pepper
12 oz. to 1 lb. spaghetti
1/2 lb. scallops
1 1/2 c. olive oil
1/2 c. shallots, finely chopped
Salt to taste