Mix the rice with the shrimp, crab meat, scallions, garlic and seasonings. Add the cracker meal to bind the mixture so that you have a moist but compact stuffing. Rinse the casings, then fit onto a sausage machine or onto the tip of a large-mouthed funnel. Stuff the mixture into the casings, occasionally pricking the casing to release any air that might have accumulated in the filling. Make links about 6 inches long, tying both ends and leaving a little room between the ties so that you can cut the links later if you wish.

When ready to eat, bring a large kettle of water to a boil and add the sausages. Boil for about 8 to 10 minutes, or until thoroughly heated. Serve immediately. Eat as you would boudin blanc and wash them down with lots of beer. Makes about 7 links, each about 6 inches long.